Ted Robinson

In nine of the last 10 seasons either St. Louis or Houston has won the NL Central. Now for the second straight year these teams meet for the National League pennant. Let's take a look at the top things to watch in the NLCS -- the latest chapter in this very competitive rivalry.

Seeking a reversal of fortunes
Andy Pettitte, Roger Clemens, and Roy Oswalt are the top three starters in the Houston rotation, and they pitched extraordinarily well for much of the regular season. But they have to pitch better against St. Louis than they did in the regular season.

Pettitte went 17-9, won his last seven regular-season decisions, and may have been the best starter in the National League over the second half of the season. Oswalt threw a career-high 241.2 innings, posting a 20-12 record with a 2.94 ERA. Clemens got virtually no run support yet still managed to win 13 games while leading the major leagues with a 1.87 ERA.

But Pettitte, Clemens, and Oswalt combined won a total of only two games against the Cardinals this season. Clemens pitched well in four starts vs. St. Louis, but had only one win to show for it. Pettitte was 0-1 in three starts against the Cardinals despite a 1.35 ERA in those games. Oswalt went 1-2 in three outings against St. Louis, but in those three starts his ERA was 5.21.

The Cardinals and Astros play each other a lot. Not only are they NL Central division rivals who have met 32 times over the last two regular seasons, they also played seven games in last year's NLCS won by the Cardinals. So the starting pitchers on both teams have faced the opposing hitters a lot, and there won't be a whole lot of surprises in the pitcher vs. hitter matchups in this series. But the pressure's on the Houston starters to handle the potent St. Louis lineup.

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Chris Carpenter's performance
Setting the tone for the NLCS in Game 1 is huge, and the Cardinals will call upon their ace Chris Carpenter, who won 21 games during the regular season, to be sharp and get them off to a good start. They could also need a quality start from him later in the series.

Carpenter started Game 1 of the NLDS against the Padres and picked up the win, throwing six shutout innings and allowing just three hits. He struck out three and walked three. That performance was more in keeping with his fine form through much of the season, and not the way he closed out the regular season which was by failing to win in his final four starts, allowing 22 runs in 21 and one third innings.

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Carpenter pitched very well against Houston in the regular season going 4-0 with a 1.85 ERA in five starts, with two of those wins coming in games when he started against Roger Clemens. The only glitch for Carpenter against the Astros was his Sept. 29 start when he allowed six runs -- five of them earned -- on nine hits in six innings. He didn't figure in the decision as the Astros won, 7-6. A glitch by Carpenter in the NLCS could be damaging to the Cardinals' hopes of a return to the World Series.