Roy Oswalt returned from the DL to make his first start since June 23 (back injury) and had mixed results against the weak-hitting lineup of the San Francisco Giants. Oswalt went six innings, striking out four, walking two and allowing three earned runs on 12 hits. He now has an ERA of 3.84 with a xFIP of 4.14. in 77.1 innings pitched this season.
While his results were underwhelming, there were some encouraging signs from the 33-year-old right-hander. Oswalt came into the game with the lowest swinging-strike rate of his career at 6.8 percent; however, he induced 11 swings-and-misses on 93 pitches yesterday. Nine of them came on his fastball, which averaged 91.4 mph against the Giants. It was a slight uptick from his 91.2 mph average this season, but bellow last season's average of 92.6 mph.
Despite the dip in average velocity, the fastball has not been Oswalt's problem this season. All three of his off-speed pitches (changeup, curveball and slider) have been less effective in 2011. Both his slider and changeup swinging-strike percentage have been cut in half, and his slider usage has dropped from 14.8 to 6.7 percent. His curveball has remained just as effective as last season, but he has also stopped throwing it as frequently (14.7 to 9 percent).
Oswalt has relied heavily on his changeup, throwing it at a 21 percent rate, a career high. Either Oswalt has not been comfortable with his breaking balls this season or he has just fallen in love with the pitch. Either way, Carlos Ruiz and Oswalt should think about incorporating more curveballs and sliders into the game plan. His fastball still has enough life to get swings and misses, but part of Oswalt's success last season was his ability to throw any one of his four pitches at any time.
There may be more to this story than I realize, but I do not think it is a coincidence that his lowest strikeout rate of his career (5.35 K/9) has come in the season when he is throwing the least amount of breaking balls. I do not think we will see a change in approach, but it might be worth watching before any Game 4 start in the NLDS.