Chatwood’s debut

21-year-old Tyler Chatwood made his major league debut for the Angels on Monday night, throwing five innings in a loss against the Indians. The 74th overall pick of the 2008 draft, who was ranked by Baseball America in February as the 76th best prospect in the majors, allowed four runs in his debut, walking four and striking out three.

Here’s how Chatwood’s repertoire was scouted, courtesy of a 2010 article on AngelsWin.com: “He has a power arm, throwing a 92-97 mph heater, a power curve, and a change-up.”

PITCHf/x data from his start had his velocity down from that scouting report; his four-seam fastball ranged from 89-94 mph. The first chart shows the spin deflection (in inches) of Chatwood’s three pitches, and the second shows spin direction (in degrees) plotted against velocity.

Based on some early-season observations, pfx_x and pfx_z values look pretty good so far in Anaheim; pfx_z might be a little bit high, but nothing crazy. With that in mind, these values should be a pretty reasonable indicator of how Chatwood’s pitches move. The fastball and the change-up move similarly, but the change is about 13 mph slower. Those characteristics could bode well for the change-up in the future.

As for some results: Chatwood picked up four swings-and-misses in his 90-pitch outing. If you think about it on a per-swing rate, his whiff rate on the night was an unspectacular 12.5 percent over 32 swings. Three of the whiffs were on his change, and the other was on the curve. The fastball was spotted for two called strikeouts, but was otherwise unimpressive: It was thrown for a ball 45 percent of the time (league average for fastballs is around 36 percent) and the Indians hit two of them for home runs.