Are the Nationals’ starting pitchers due for a regression?

PHILADELPHIA - Since the beginning of the season, as the Nationals’ starting pitchers continued to pile up solid, if not spectacular, outings and keep the team in position to win games despite ranking last in baseball in strikeouts, observers have wondered if the group was really this good, or if their success was merely an aberration.

The politically correct term in sabermetric circles is “regression to the mean,” which is a nice way of saying, “You’re not really this good, right?” Essentially, baseball people who use that term are saying that history suggests the Nationals have an average staff, they’ve been performing above-average so far and with enough time and data, they’ll come back to that average.

We don’t know yet if that’s happening, or if the 17 earned runs the Nationals gave up in three games against the Phillies - all but one of them surrendered by starting pitchers - are an isolated slip-up. But the rules of pitching would suggest the Nationals’ starters are due for a slide.

One reason the group has been so good this year is because it hasn’t beaten itself; the Nationals’ starters have the sixth-lowest rate of home runs per nine innings in the game, and that’s after allowing three bombs in three days to the Phillies. They’ve also been extraordinarily good at not walking people; their walks-per-nine-innings rate is the fifth lowest in baseball. If that doesn’t last, they could be in trouble.

The reason so many people are hard on the Nationals’ staff is the low strikeout rate. Essentially, strikeouts act as a buffer; if a pitcher is able to miss bats, he’s shielded from things like bad defensive plays, winds that turn ordinary fly balls into home runs and unfriendly strike zones from umpires - essentially, all the things he can’t control. If he throws a pitch, and a batter swings and misses it, he’s controlled the situation and eliminated any variables.

Pitchers are going to have bad nights and bad luck, but strikeout stuff helps minimize the damage. That’s what elite pitchers like the Phillies’ Roy Halladay do so well. They might have one bad inning, like Halladay did in the fourth last night, but they’re able to shut things down after that. Halladay struck out 10 in seven innings.

Washington’s starters, though, have the lowest swing-and-miss rate in baseball (at 6.2 percent of pitches), and aside from Jordan Zimmermann, there’s nobody on the staff with strikeout stuff. Even Zimmermann has been striking out fewer batters this year, getting more of his outs with ground balls. If hitters start to turn on pitches for home runs and the Nationals start walking batters, things could get ugly.

Now, there’s also a school of thought - and this is the one the Nationals subscribe to - that the ability to consistently get ground balls is an art. Nationals pitching coach Steve McCatty scoffs at the idea that strikeouts are necessary to great pitching. In today’s era of strict pitch counts, they’re certainly an expensive way of doing things. And there are pitchers like Greg Maddux who can rely on deception and timing to be great with modest strikeout totals. But pitchers like Maddux are rare; in fact, there may not be another Hall of Fame pitcher like him.

It’s worth noting that two of the three pitchers who started against the Phillies - Jason Marquis and John Lannan - have horrible career numbers in Philadelphia. And with the Phillies’ slugger-filled lineup playing in a hitter-friendly park, it’s certainly more likely that opposing pitchers will give up some homers in a three-game trip to Citizens Bank Park. But that’s where strikeouts help; they take contact, and cheap home runs, out of play. It should also be mentioned that the Nationals’ pitching dropoff came in a series where they made just one error.

Washington starts a three-game series in Florida tonight, and while Zimmermann (tonight’s starter) has been superb against the Marlins, he’s been about the only one; the Nationals are 15-41 against the Marlins since the start of the 2008 season. And with the team’s offense in a long rut, well, this would be a bad time for the starters to slip.

Essentially, if the Nationals are defying baseball logic by showing that pitch-to-contact stuff can be effective through an entire season, now would be a good time to continue it. And if their staff is due for a fall, now would be a good time to postpone it.