There's a big weekend in the NL Central, where the top four teams will square off in a two battles of surprises vs. favorites. The Reds travel to St. Louis, while the Astros and Pirates continue a four-game series at Enron Memorial Field (the Astros won the opener, 3-1, behind Roy Oswalt).

I'm probably giving the Pirates more credit than they deserve by including them in this piece. While their 12-5 start generated a lot of positive press and some ridiculous accolades for Lloyd McClendon, their subsequent 7-15 stretch is a better indication of the talent in place. They have the worst offense in the game, with three, maybe four major-league-caliber regulars in the lineup. An effective middle-relief corps and a strong defense enabled them to win more than their share of low-scoring games, but there's just no way to be a contender while struggling to score four runs a game. By the time they leave Houston, the Pirates should be old news.

Meanwhile, the Astros are finally putting something together, with their first four-game winning streak of the year. They've had the reverse of the Pirates' problems, with a very good rotation getting little support from its middle relief, although the bullpen has shown signs of coming around, in part thanks to Octavio Dotel's improvement (six shutout innings in his last five appearances). While Wade Miller has been missed, the work of Carlos Hernandez and Dave Mlicki–both among the top 30 starters in baseball according to Support-Neutral measures–has given the Astros a front three that has quietly been among the best in the league.

There's a perception that the Astros' problem is at the plate, but the team is sixth in the NL in Equivalent Average and third in runs scored. Part of the problem is the top of the lineup, where Craig Biggio and the team's catchers (Brad Ausmus andGregg Zaun) have combined for an OBP of about .310. Rumblings that Biggio might be done have surfaced, thanks to his .224/.315/.392 start. Biggio is striking out at a career-high pace (29 in 143 at-bats), and walking less (10 times) than he ever has previously.

The fact that Biggio's power is still pretty much intact leads me to believe that this is a slump, and something from which he will bounce back. In this particular case, the strikeouts and batting average are the things to watch. If Biggio keeps trading singles for swishes, it will be a sign that his bat speed is shot, and that his days as one of the Killer Bs are done.

The more interesting series is between the Reds and Cardinals. The Reds are the best story in baseball right now, just as they were in 1999. At 25-15, they lead the Central by five games, and have the second-best record in the NL. It's all about the bullpen in Cincy; they have the eight-best EqA in the league, and a barely-above-average rotation, but the best relief pitching in the game, led by Gabe White. No Reds reliever has been a below-average performer to date.

Better known is the Reds' outfield situation, which hasn't suffered nearly as much from Ken Griffey's absence as everyone thought it would. Juan Encarnacion hasn't been a disaster (.276/.325/.513), while Austin Kearns has taken been a monster (.392/.524/.658, with 18 walks in less than 100 plate appearances since being called up.

Really stupid polls aside, Encarnacion is the guy who has to go to the bench when Griffey returns. His best use is as a fourth outfielder–Griffey's legs–and spot-starter for Dunn, Griffey, or Sean Casey against some left-handers. If the Reds allow the best six weeks of Encarnacion's life to push them into bad decisions, they may blow their shot at a division title.

The Cardinals are having their best week of the season; not just on the field–where they finally got back to .500–but in the trainer's room, which appears to be free of Woody Williams and Garret Stephenson. Williams certainly looked healthy in shutting down the Cubs for six innings Wednesday night, and the Cardinals desperately need him to stabilize the rotation behind Matt Morris and Darryl Kile (who isn't 100% himself, and seems certain to be disabled before long).

Like the Reds, the Cardinals are supporting a so-so rotation with a fine bullpen, thanks to Jason Isringhausen and Mike Timlin. The loss of Steve Kline has hampered Tony LaRussa's ability to chase matchups, but perhaps led to better performances by the pen as a whole. With only Mike Matthews as a trustworthy southpaw, LaRussa has been letting his relievers go a full inning more often, and has used multiple relievers to get through an inning much less frequently. It will be interesting to see if LaRussa learns from the Cards' recent success and sticks to this usage pattern when Kline returns.

More important to the Cardinals' future is adding some offense at the bottom of the lineup. It's the rare team that has to addKerry Robinson to the mix to generate runs, but with Placido Polanco hitting an empty .260, that's just what the Cards have done. Robinson is playing well by his standards–.288/.339/.423–but the Cards will need to find a left fielder or third baseman going forward, especially since they insist on playing the Mikes (Matheny and Difelice) behind the plate every day. (No, Mike Matheny isn't going to sustain his .266/.326/.430.)

Both the Reds and the Cardinals go into their series having won four straight, mostly by beating up the weak sisters of the division, the Cubs and Brewers. Those two teams also play this weekend, in a series that will no doubt feature a dozen sacrifice bunts and maybe even that many runs.