Second chances. That's the theme of the National League playoffs this season, and St. Louis, Atlanta, Houston or San Diego is going to take advantage of their most recent opportunity and hopefully turn it into a World Series championship.

For St. Louis, 2005 is a chance to redeem itself for a runner-up finish last season. For San Diego, the postseason is a chance to prove that they're not as bad as people think (even though they enter the playoffs with the worst winning percentage of any division winner since 1969).

For Houston, this is another chance to topple the Cardinals, whom they've finished behind for the division title and the pennant in each of the last two years. For Atlanta, this is more like a 14th chance. The Braves are trying to once again validate their spot among baseball's all-time elite with that elusive World Series ring.

Here's a closer look at the National League Divisional Series (series odds in parentheses):

St. Louis (-400) vs. San Diego (+300)

Even though on paper this series appears to be a tremendous mismatch (it is) I throw out this warning: the playoffs truly are a whole new ball game. The Cardinals (100-62) are 18 full games better than the Padres (82-80) thus far in 2005, but now each team enters Game 1 on Tuesday afternoon as 0-0. It's trite, but true. Consider: the National League Wild Card had knocked off the regular-season champion five times in the last six seasons.

Chris Carpenter (21-5, 2.83 ERA, 213 strikeouts) has been truly dominant for St. Louis this season, giving them the ace they seemingly lacked over the past few years. He will take the ball for Game 1, opposed by San Diego's Jake Peavy (13-7, 2.88, 216 K's). Game 2 should see key free agent acquisition Mark Mulder (16-8, 3.64) toeing the slab for the Cards against either Pedro Astacio (2-0, 1.89 ERA in September) or Woody Williams (25-8, 2.91 ERA in St. Louis).

In 2004 St. Louis went down in history as "The Team That Lost To The Red Sox" in the World Series. They posted their first back-to-back 100-win seasons since 1944, and have seemingly been penciled into the postseason since April. With Albert Pujols (.330 BA, 41 HR, 117 RBI, 129 runs), the Cards have one of the game's most feared hitters. Do-it-all centerfielder Jim Edmonds (.385 OBP, 29, 89) has shaken off some nagging injuries of his own and will be ready to mash.

San Diego has been a paradigm of mediocrity and almost entered the postseason with a sub-.500 record. In fact, they actually finished with the 7th best mark in the NL, and were only one game better than the Brewers. Offense has been a problem for the Fathers, who are 25th in the Major Leagues with a .258 team batting average. Yet, despite their flaws, the Padres actually won the season-series between these two teams (4-3), including a sweep back in May. Brian Giles has abused the Cardinals so far this year, hitting a robust .417.

Atlanta (Even) vs. Houston (-120)

This series is a rematch of the outstanding five-game chess match that the Astros (89-73) and the Braves (90-72) endured just last year. You may remember that series because Carlos Beltran hit about 18 home runs in those five games and parlayed that week into a $119 million payday with the Mets.

This series should be the most competitive of any because it features some monster pitching matchups. Game 1 begins in Hotlanta on Wednesday, and should be a gem between two playoff veterans - Tim Hudson (3.44 career playoff ERA) and Andy Pettite (13-8 career playoff record). Hudson was the Braves' prized free agent pickup last winter, having proven himself as an Oakland ace over the last five years. Pettite is 4-1 with a 3.46 ERA in seven career starts against Atlanta, hasn't surrendered more than three runs since June, and has been one of the best Big Game Pitchers over the last decade.

Game 2 will feature a pair of Hall-of-Fame hurlers when John Smotlz (14-7, 3.06) meets Roger Clemens (13-8, 1.87) in Turner Field. Smotlz is making his 27th postseason start, and he owns a record 14 playoff wins. He is 6-0 with a 2.68 ERA in 14 Division Series appearances, and the Braves have lost just three of his last 20 starts. Clemens is, well, he's Roger Friggin' Clemens (I could rattle off a number of stats here, but my editor wants me to keep it under 12,000 words). Smotlz has been bothered by a sore shoulder and elbow, but has vowed that nothing will keep him from taking the hill.

Despite their ridiculous 14 consecutive postseason appearances - all via a division title - the Atlanta organization is still haunted more by their postseason failures than glorified for their regular season brilliance. However, the 2005 version of the Braves has a distinctly different vibe to it. Andruw Jones (.262, 51, 128) and Chipper Jones (.293, 20, 71) are now the cagey veterans on a club whose run to the postseason was ignited by an infusion of youth - particularly the addition of the one they call The Natural, Jeff Francoeur (14 HR, 49 RBI in 69 games). But what Atlanta lacks in "experience" is makes up for with talent and a nave desire to prove that these aren't the Braves of old.

Houston became the first team in baseball history to make the playoffs after being 15 games under .500 at some point during the season. They were a pathetic 15-30 back in May, but finished 74-43 the rest of the way to hold off the Phillies and earn the final playoff spot. Runs have been at a premium (.256 batting average was 27th in the Majors) for the Astros, but they've been able to score when they need to. Lance Berkman (.295, 24, 82) is ever dangerous, and Morgan Ensberg (.282, 36, 100) has been one of the league's biggest surprises in 2005.