The Cardinals have finished in first or second in the National League Central in each of the past six years. Since the end of the 20th century, the Cardinals have been first or second every year but 2003, 2007, and 2008, and 2007 was the only year they didn't have a winning record. Starting in 2000, their .563 winning percentage is the best in the National League, 28 games ahead of Atlanta and 70 ahead of Los Angeles.
Yet, there are reasons to think their reign could be nearing an end. As Travis Sawchik pointed out Monday in the Pittsburgh Tribune, the team has key players (Adam Wainwright, Yadier Molina, Matt Holiday, and Jhonny Peralta) over 30. Third baseman Matt Carpenter will turn 30 in November. The Cardinals' weighted average batters' age is 29.0, older than the Pirates (27.8) and Cubs (27.2). Their farm system's good--ESPN's Keith Law ranked the Cardinals 13th overall--but the up-and-coming Pirates and Cubs rank higher (seventh and first, respectively). And, of course, Wainwright, one of the best pitchers in baseball, is lost for the season with torn Achilles tendon.
Several players have started slowly. Jason Heyward, acquired in a trade with the Braves and entering his free agent year, is batting .217 with a .261 on base percentage and .349 slugging percentage. Molina's slash line is similarly punchless, .246/.306/.308. Mark Reynolds, expected to platoon at first with Matt Adams, is hitting .172 with one homer. Starter John Lackey's got a 4.21 ERA and the 10th-lowest strikeout rate in the league, and of course Wainwright and his 1.44 ERA are lost for the season.
So of course they're second in the league in batting average (.274), second in on base percentage (.339), and fourth in slugging percentage (.408). Of course they lead the league in overall ERA (2.43), starters' ERA (2.85), and bullpen ERA (1.59). Of course they're tied with the Mets for the most wins in the National League (15), they have the best winning percentage in baseball (.714), they lead the Central by 2.5 games, and they have easily the best run differential in the league (+37: 92 scored, 55 allowed). Were the season to end today, a pretty good case could be made for Carpenter for MVP, as he's first in the league in doubles (13) and runs (21), second in slugging percentage (.651) and OPS (1.089), fifth in batting average (.372), and eighth in on base percentage (.438).
In short, they're clearly the best opponents the Pirates have faced this year as they open a weekend series at Busch Stadium. The Pirates will face Lance Lynn (1-2, 3.63 ERA), Lackey, and Michael Wacha (4-0, 2.42 ERA). The Pirates' bats have shown signs of life of late (they're fourth in the league in runs scored over the past two weeks), and they'll need them against a Cardinals pitching staff that's been pretty formidable so far this year.