Strasburg's fastball doesn't rack up K's

Stephen Strasburg starts tonight for the Washington Nationals, and he's having a good season despite the 3-6 record: He has a 2.50 ERA, .208 batting average allowed and .591 OPS allowed. He's 15th in the majors in lowest batting average allowed and 14th in lowest OPS allowed, although the ERA is a little misleading because nine of the 31 runs he's allowed are unearned.

Still, other than missing two weeks with that strained forearm, he's not the reason the Nationals have disappointed.

The odd thing about Strasburg's season, however, is that while he's tied with Matt Harvey for highest average fastball velocity among starting pitchers at 95.4 mph, it hasn't been a great strikeout pitch for him.

The qualified starting pitchers with the highest percentage of strikeouts off their fastballs:

1. Yu Darvish, 36.0

2. Shelby Miller, 30.3

3. Max Scherzer, 28.8

4. Anibal Sanchez, 27.3

5. Kyle Kendrick, 26.3

Kendrick's name is a surprise, but the others are high-strikeout guys you would expect to see. Harvey is ninth at 23.6 percent.

Strasburg? He's 74th with a strikeout percentage of 10.7 percent, below guys like Dillon Gee, Paul Maholm and Joe Blanton.

OK, maybe he just doesn't throw his fastball much with two strikes. But even his swing-and-miss percentage off his fastball ranks just 47th at 14.3 percent. In plate appearances ending with a fastball, Strasburg has allowed a .725 OPS, which ranks 38th among starters. Compare that to Harvey, who has allowed a .581 OPS off his fastball, or Miller, at .574. (Cliff Lee has the lowest OPS allowed on his fastball at .495).

Left-handers, in particular, don't have much of a problem seeing the fastball. They're hitting .280 off it with 14 walks, nine strikeouts and seven extra-base hits. Strasburg is nearly as likely to allow an extra-base hit as record a strikeout when throwing a fastball to left-handed batters, which isn't would you expect from a guy who throws 95.

That doesn't mean the fastball isn't a weapon. He still uses it set up his other pitches. Batters are hitting .159 off his curveball, with 23 strikeouts and one walk, and .080 off his changeup (4-for-50 with 31 strikeouts). While those are vicious pitches, they wouldn't be effective without a 95-mph heater.

Still, it makes you wonder if Strasburg will eventually attempt to develop more of a cut fastball, or maybe a two-seamer with more sink. Or maybe hitters just see the pitch out of his hand too well. As we've seen with Pirates rookie Gerrit Cole -- who has three strikeouts in two games despite throwing in the upper 90s -- velocity isn't everything. Movement and deception are just as important.

Strasburg certainly has a feel for pitching. But the scary thing for opposing hitters is there's still room for improvement.