After yesterday's game, that's the Cubs' record this year in one-run games, 13-19, good for a .406 winning percentage. The only team that's a contender and has a worse winning percentage in one-run games is Boston, who at 7-11 have played at a .389 clip.

Cursed?

Of course not. The Cubs were exceptional in one-run games last year (27-17, .614), but things haven't gone their way this year. I'm going to guess (and then research my guesses a bit) that the Cubs' poor record in one-run games (a big reason why they aren't vying for the division crown and/or leading the wild-card race) is due in part to some combination of the following:

1) pitching in the late innings
Before checking, I thought this would be a problem -- that the Cubs' bullpen just wasn't good, or that the starters broke down quickly in late innings. It certainly is true that we remember painful moments in the late innings, but the stat sheet says that overall this just hasn't been the case. The Cubs have a 3.49 ERA after the sixth inning, good for fourth in all of baseball (the Cardinals easily lead the majors with a 2.74 ERA). The Cubs have the third best WHIP (1.24) in these situations, the third-best K/9 (8.19), and the best Batting Average Against (.221). The Cubs pitching in the late innings simply hasn't been bad; if anything, it has been an asset.

2) offense in late innings
Joe Sheehan over at Baseball Prospectus has posited that one reason the Cubs have struggled more than expected is their mostly-righty lineup. Having an "unbalanced" lineup would theoretically leave a team more susceptible to unfavorable bullpen matchups, since an opposing team could throw out their great right-handed reliever and let him cruise through the heart of the Cubs' order.

This theory sounds great, but doesn't hold any water in practice. Despite having a bunch of righties with historically better averages against lefties, this year's Cubs are dramatically better against right-handed pitching. They've hit the second-best in the league against righties this year (276/332/479, second to Colorado), while having the worst OPS in the NL against lefties (231/302/355).

Furthermore, the Cubs have similar offensive splits in innings 1-6 (268/325/464) and 7-9 (266/327/435). It just isn't the case that the Cubs' offense gets shut down in late innings.

3) luck
This is what I'm left with, and I hate that. I can't research it. I can't argue for or against it. It just seems that this is the way the cookie's crumbled so far. The Cubs are losing the close ones, winning the blowouts (17-7 when the run differential in the final score is 5 or greater), and find themselves behind in the wild card chase.

Hopefully the luck will change, or maybe the gods really have conspired against Chicago and Boston this year. If you have any other ideas for why you think the Cubs have struggled in one-run games, drop a note in the comments.