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One start in the books for Justin Masterson. Five innings, four hits, two walks, and five strikeouts, allowing only one earned run.
Last season, between the Red Sox and Indians, Masterson put up 119 strikeouts in 129.1 innings (8.28 K/9).
While much of that work came out of the bullpen for the Red Sox, it did give us an indication of what type of potential Masterson had should he harness his command.
The one thing that is clearly evident from watching Masterson pitch is that he has a lot of movement to his two-seamer and sinker. He used both fastballs in 80 out of 92 pitches yesterday.
Pitch f/x data from yesterday's game show his two-seam fastball moving about 10 inches in toward a right-handed batter or away from a left-handed batter and just over one inch downward. His "four-seam" fastball, which acts more like a sinker, broke over five-and-a-half inches downward and almost eight inches in to a right-hander.
His third pitch is the slider, which wasn't as sharp last night as it has been in the past, but he did throw it 12 times and generated three swings and misses from those 12 pitches.
Swings and misses combined with ground balls will be the key to Masterson's success in 2010. For two years running Masterson has been able to get batters to swing and miss at an above league average rate and has had ground ball rates of over 50 percent. Both are good indicators, but both will need to hold up to a full season in the rotation.
In last night's ball game Masterson generated 12 swinging strikes and seven ground balls—a good base that he can work off as the season moves forward.
Another positive note about Masterson's transition to the rotation is that he hasn't lost much velocity. We've seen this happen from C.J. Wilson, who was routinely hitting 93 mph as a reliever but topped out at about 91 mph yesterday and sat mostly around 89-90 mph.
Joba Chamberlain is perhaps the more famous example. He was throwing 97 mph on average with his fastball before switching to the rotation, where he saw his average velocity drop to 92.5 mph last season.
The three issues to be most concerned about are command (4.18 BB/9 and 128 hits last season), the lack of a big-time third pitch, and his splits against left-handed batters.
His two fastballs are relatively equal in velocity but move quite differently, so his slider is his only true offspeed offering. Masterson has been extremely effective against right-handed hitters in his career, but lefties have given him some trouble. An improvement in command would go a long way to helping those numbers.
We have a lot of positive indicators for success from Justin Masterson this season. He has two nasty fastballs that should generate plenty of ground balls, and unlike his teammate Fausto Carmona, Masterson has the ability to miss bats as well. Look for more positive outcomes in 2010.