The Pirates are working their way toward not only their first winning season since 1992, but also a playoff berth. Thus far, a 2012-style collapse has eluded them, and this year's model is certainly a better team on the merits than last year's. With that said, one possible concern for the Pirates is that the bullpen -- one of baseball's very best this season -- has been worked fairly hard.
That's largely a function of the fact that rotation, while excellent in terms of run prevention and on a rate basis, doesn't tend to work deeply into games. For instance, this season Pittsburgh starters have averaged just 5 2/3 innings per start, which ranks 24th among MLB's 30 teams. Obviously, the remaining burden falls on the bullpen.
Insofar as that burden is concerned, let's take a look at some numbers:
|Pirates' bullpen workload in 2013 (MLB rank in parentheses)|
|Appearances||Innings pitched||Pitches thrown||Batters faced||Pitches/Appearance||>1IP|
|373 (20th)||451 (3rd)||7,047 (7th)||1,851 (5th)||19.0 (T-3rd)||113 (7th)|
As for the categories above, from left to right we've got total relief appearances by the Pirates this season, bullpen innings, total pitches thrown by Pirate relievers, total batters faced, average number of pitches per relief appearance and finally the number of individual relief appearances that lasted longer than one inning.
As you can see, the Pirates rank near the top of the league in all measures except total appearances. Plainly put, this is a bullpen that's being ridden hard by manager Clint Hurdle. That's not a criticism of Hurdle, mind you, as he's doing what he can tactically to win every game he can. To state the obvious, the Pirates simply aren't in a position to "pump the brakes" and assume a playoff berth.
Still, these are usage patterns that could exact a price over the final month of the season. While the Pittsburgh pen isn't the hardest-worked unit in baseball, it is rather easily the hardest-worked contending bullpen in all of baseball. That's especially the case once you consider that they're still without the services of closer Jason Grilli (forearm injury).
So, Red flag? Maybe not quite. After all, Pittsburgh relievers -- chiefly the core of Mark Melancon, Tony Watson and Justin Wilson -- may be perfectly capable of shouldering such demands, or the effects of those demands may not be felt until next season. With that said, the performance of the Pittsburgh bullpen bears monitoring as we head down the stretch and into the postseason.