The 101st World Series includes two teams in the Astros and White Sox that, entering this season, not only weren’t expected to reach late October, but weren’t even expected to win their respective divisions. Having some of the best pitching in baseball, though, has allowed both teams to steamroll through the playoffs, proving critics wrong.

As the Wild Card representative in the National League, the Astros can become the fourth team in as many years to win the World Series without winning a division. And though the city of Houston may not admit it, just making the World Series for the first time in the history of the franchise is an accomplishment of its own. While Chicago does have a World Series history, it is not long. The White Sox most recently had a chance to win it all in 1959, when they lost the Series to the Dodgers, and the last year they won the World Series was in 1917.

The biggest storyline of the American League Championship Series was the dominance of the White Sox starters, who, after a Game 1 loss, pitched four consecutive complete-game wins, becoming the first team to do so in the postseason since the 1956 Yankees. As impressive as Chicago’s bullpen abandonment was, no single White Sox pitcher enters the World Series with as much respect or past success as any member of the Astros’ daunting ace machine that includes Roger Clemens, Andy Pettitte and Roy Oswalt. While Clemens and Pettitte are postseason veterans, Oswalt will be making his first World Series appearance. But by winning two games in the National League Championship Series — including an outstanding performance in the series clincher following his team’s incomprehensible Game 5 loss — Oswalt, still unbeaten in six career postseason starts, proved that he can handle playoff pressure.

Sox starter Jose Contreras, who allowed six runs over 17 1/3 ALCS innings, has matured immeasurably since his days as a big-game bust with the Yankees, and is being trusted, justifiably, with a Game 1 start against Clemens. Games 2 and 3 (Pettitte vs. Mark Buehrle; Oswalt vs. Jon Garland) will likely be decided late, but Chicago holds a clear edge in Game 4, starting Freddy Garcia against Brandon Backe.

Both teams lack power on offense, instead manufacturing runs with a small-ball approach rarely seen in the American League. While any edge may not be drastic, the White Sox do hold an advantage over the Astros offensively. Should seven games be played, Houston will have to play four on the road, where an alarming number of Astros batters hit far worse than at home this season. Craig Biggio hit .295 at Minute Maid Park this year, but just .235 on the road. Shortstop Adam Everett’s road average was .216, compared to .282 at home. Catcher Brad Ausmus hit .280 at home, but only .237 on the road, while Jason Lane (.298) nearly reached .300 in Houston, but managed just a .239 average away from home.

Lance Berkman and Morgan Ensberg are major threats, but without runners on, they’re far less intimidating. The White Sox, conversely, have pests at the top of the order in AL stolen-base runner-up Scott Podsednik and Japanese import Tadahito Iguchi, complemented by sufficient power in Paul Konerko — Ensberg’s equal — and Jermaine Dye. Third baseman Joe Crede, suddenly erasing regular-season fan and media gripes with a stellar postseason, adds punch to the bottom of the lineup.

Each bullpen could struggle more than expected, but for contrasting reasons. The strength of Chicago’s rotation during the ALCS made just two-thirds of an inning from Neal Cotts the only necessary relief work from the Sox in the series. But whether the rest will hurt or help Chicago may not ever be known if the team’s starters can pitch as deep into games as they did against the Angels. For Houston, Brad Lidge’s blown save in Game 5 gets perhaps more attention than it deserves, but by setting the Cardinals up with runners on first and third with nobody out in the ninth inning of Game 4, he nearly surrendered a one-run lead in what was likely the most important game of the series. Lidge’s most breathtaking pitch is his slider, which was fatal in the 2004 postseason, very effective throughout the 2005 regular season, but at times has been flat and entirely hittable this October, possibly due to the closer’s appearance in more games than necessary down the stretch.

This series will be controlled by pitching from the start, and could closely resemble the 2001 World Series, which went seven games and featured a Yankees team that had three pitchers with a sub-4.00 ERA and a Diamondbacks team led by future Hall of Famers Curt Schilling and Randy Johnson. And as in that series, the team with home-field advantage this time may find a way to put together just enough hits to win a decisive game.

To the surprise of very few, the Cardinals had no problem with the Padres in the Division Series, completing a three-game sweep and resting for the National League Championship Series, which will match them up against the Astros for the second straight year. In last season’s NLCS, home-field advantage proved crucial, as the home team won each of the seven games and the Cardinals advanced to their first World Series since 1987.

Missing from this year’s series will be Carlos Beltran, who carried the Astros to within a game of their first World Series appearance as a franchise last season, but signed with the Mets in the offseason. Houston hasn’t replaced the power Beltran provided, but it has better pitching than last year’s team, now that Andy Pettitte is healthy and having one of his best seasons.

But St. Louis may have improved its pitching even more since last year, trading for Mark Mulder and benefiting from a Cy Young-caliber season by Chris Carpenter, who missed last October with a biceps strain. Game 1 will match Pettitte against Carpenter at Busch Stadium, starting off what could easily be a seven-game series.

Houston’s bullpen proved its worth in the Division Series, particularly in a series-clinching, 18-inning Game 4 win in which seven pitchers combined to allow just one run over 13 2/3 innings. Roger Clemens came out of the bullpen on two days’ rest and earned the win, pitching three scoreless innings and allowing one hit, sriking out four.

Cardinals closer Jason Isringhausen finished the Division Series strong, bouncing back from a shaky Game 1 performance in which he recorded the game’s final two outs, but only after allowing a run on four hits. But even on his best day, Isringhausen can’t match the brilliance of Astros closer Brad Lidge, who made a name for himself in the 2004 playoffs and pitched four scoreless innings in this year’s Division Series. In last year’s NLCS, Lidge made the Cardinals’ offense, that team’s strength, a complete non-factor by allowing a single hit over eight scoreless innings in which he struck out 14 and walked two. If Houston’s starting trio of Pettitte, Clemens and Roy Oswalt are able to hold down this year’s Cardinals — who don’t have as powerful an offense as last year’s team — long enough to hand a lead to their closer, Lidge will be the one to carry the Astros to the World Series.

For only the second time since 1997, the American League Championship Series includes neither the Yankees nor the Red Sox, who both suffered surprising defeats in the opening round, setting up a long offseason in two baseball-driven cities. The White Sox had three days off between their series-clinching win over the Red Sox and the opening game of the ALCS, while a Game 5 victory celebration and a late flight gave the Angels no more than a few hours of sleep before Game 1. But the lack of rest didn’t hurt the Angels, who managed enough offense off White Sox starter Jose Contreras to make a winner of Paul Byrd, who was pitching on three days’ rest.

While a second straight home loss to open the series would hurt the White Sox in Game 2, it would not drown their chances at a series win. Even with Contreras and Game 2 starter Mark Buehrle having been used, Chicago’s starting staff is too deep to be pushed aside. With Jarrod Washburn, who missed his scheduled ALDS Game 4 start with strep throat, starting Game 2 opposite Buehrle, who held the Red Sox down in a critical ALDS Game 2, the White Sox should make the trip to Anaheim with the series even.

Bartolo Colon’s absence from the ALCS roster with an inflamed right shoulder could be more helpful to the Angels than the White Sox because his replacement, Ervin Santana, pitched fearlessly in the deciding fifth game of the ALDS, holding the Yankees to three runs over 5 1/3 innings for the biggest win of his rookie career. In his second big league start, Santana limited the White Sox to five hits in a complete-game shutout win on May 23.

The Angels proved in the Division Series that they could win more games than they lose even without sparkplug Chone Figgins and relentless powerhouse Vladimir Guerrero playing at their best. Figgins, who stole a Major League-leading 62 bases this season, went 3-for-21 (.143) without a steal in the five games against the Yankees, while Guerrero batted .333, but had no extra-base hits all series.

But even if the White Sox can’t contain Figgins and Guerrero, they should feel confident in a bullpen that allowed the Red Sox just four hits over 7 1/3 scoreless innings in the Division Series. The difference-maker could be Orlando Hernandez, who was a playoff staple for the Yankees throughout their most recent dynasty and is 9-3 with a 2.57 ERA in 105 career postseason innings. Hernandez already added to his legend this year with a remarkable performance in the sixth inning of Game 3 of the Division Series, when he relieved Damaso Marte — who had loaded the bases with Red Sox before getting an out — and induced two popouts and a strikeout to get out of trouble and keep the lead in Chicago’s hands. Hernandez worked two more innings before Bobby Jenks earned his second save of the series and ended Boston’s season.

Francisco Rodriguez should scare the White Sox more than Jenks does the Angels, but with stronger starters, the White Sox — like the Astros in the NL — have the ability to make their opponent’s closer a non-factor by taking a lead into the late innings for a bullpen that has yet to allow a run this postseason.

After clinching the American League East at Fenway Park on the season’s next-to-last day, the Yankees are set to open up the American League Division Series on the road against the Angels, starting Mike Mussina in Game 1 against AL Cy Young candidate Bartolo Colon. While Mussina hasn’t pitched with much consistency over the last two months, he could receive enough run support to beat Colon, who allowed four home runs to Alex Rodriguez across six at-bats this season, including three on April 26.

Possibly the most interesting pitching matchup of the series comes in Game 2, when John Lackey will oppose New York’s Chien-Ming Wang. Although he was overshadowed by Colon’s 21 wins this season, Lackey finished with comparable — if not better — numbers than the staff ace in many areas. Lackey won just 14 games, but struck out 199 batters, ranking third in the AL, and his ERA of 3.44 was slightly lower than Colon’s. Lackey also allowed half as many home runs (13) as Colon (26).

Despite missing two months with shoulder inflammation, Wang has proven to be one of the Yankees’ most reliable starters in his rookie season, using his above-average sinkerball to induce weak ground ball outs.

For Game 3, the teams will head to Yankee Stadium, where Randy Johnson will face Angels veteran Paul Byrd. Waiting until the third game of the series to use their ace should not concern the Yankees because Johnson pitched much more comfortably at home this season, going 11-2 with a 3.13 ERA compared to 6-6 with a 4.64 ERA on the road.

The Angels have built a reputation for owning one of baseball’s best bullpens. A late-season slipup was quickly forgotten, and while Francisco Rodriguez isn’t quite up to Mariano Rivera’s level, he’s proven he can handle the Yankees, recording five saves in six opportunities against New York this season.

In Chicago, the White Sox will be the first obstacle hoping to disrupt the Red Sox’s ambitious quest to win back-to-back World Series titles, sending Jose Contreras against Matt Clement in Game 1. Although Contreras won 11 games after the All-Star break and each of his last eight starts — over which he had a 2.09 ERA — his career struggles against the Red Sox can’t be overlooked. The right-hander won his only start against Boston this season, allowing three runs over 5 2/3 innings, but is 2-4 with an 11.67 ERA throughout his career against the Sox.

Since opening the season with nine wins in his first 10 decisions, Clement has faltered, allowing four or more runs in eight of his last 16 starts.

Game 1 aside, Chicago holds an edge over Boston in the rotation based on the work of Mark Buehrle, Jon Garland and Freddy Garcia, who each compiled a sub-4.00 ERA and collectively won 48 games this year.

Neither team’s bullpen appears in postseason shape, with Chicago’s Dustin Hermanson having been replaced as the team’s closer due to back pain despite earning 34 saves in 39 chances. With Keith Foulke, one of 2004′s postseason heroes, sidelined or ineffective almost all year, Mike Timlin has been forced into the closer role, which he has handled adequately. The bigger question for Boston has been the rest of its bullpen, which was desperate enough to promote 2005 draft pick Craig Hansen down the stretch.

But Boston’s bullpen may ultimately receive the help it needs from an unlikely source. In the 2002 playoffs, Rodriguez broke out as a 20-year-old rookie, helping the Angels to a World Series title. The next year, Josh Beckett did the same in his second full season, baffling the Yankees in the Bronx to clinch the Series. Jonathan Papelbon — who struck out 34 batters in as many innings this season, allowing just two earned runs in 14 September and October innings for a 1.29 ERA — has the talent to make himself equally famous by stabilizing Boston’s bullpen and carrying the Red Sox deep into October.

In the National League, NL Cy Young hopeful Chris Carpenter and the Cardinals will host Jake Peavy and the Padres in Game 1. On this season’s final strikeout list, Peavy (216) and Carpenter (213) finished two and three, respectively, in the Majors, behind only Minnesota’s Johan Santana (238). Even if Peavy is able to outduel Carpenter — who went 2-1 with a 5.73 ERA in five September starts — and give the Padres a 1-0 series lead, St. Louis’ starters for Games 2 and 3 — Mark Mulder and Matt Morris — combined to win twice as many games this year (30) as Pedro Astacio and Adam Eaton, who will start for San Diego in those games and likely struggle to subdue the Cardinals’ always-potent lineup.

While the Braves have won the NL East for 14 consecutive years, they’ve won the World Series just once — 1995 — across that span, and have made it past the Division Series only one time since losing the 1999 World Series to the Yankees. In last year’s Division Series, the Braves lost in five games to the Astros, who will again represent the NL Wild Card and start their playoff run in Atlanta.

The Braves may have added Tim Hudson to this year’s rotation, but the trio of Andy Pettitte, Roger Clemens and 20-game winner Roy Oswalt could prove too powerful to match, as shoulder pain forced John Smoltz to miss his final start of the regular season. The Astros have at times spoiled brilliant performances by their starters by scoring few or no runs at all, but with Pettitte lined up to start two games if necessary and Brad Lidge closing games out, Houston has more than enough to feel safe, even without home-field advantage. Only Contreras won as many games after the All-Star break (11) as Pettitte, whose 1.69 ERA since the break helped hold opponents to a .201 batting average. Although Clemens battled a tight hamstring over the second half of the season, he still led the Majors with a 1.87 ERA, beating the runner-up — Pettitte — by over a half-run.