Fastball Velocity Dip, Location Concerning for Vogelsong

After declining to exercise Ryan Vogelsong's $6.5 million salary for next season, the San Francisco Giants came to terms with the 36-year-old left-handed starter Friday afternoon on a one-year contract worth $5 million, . Missing a handful of starts in the middle of 2013 with a broken hand, Vogelsong finished with a 5.73 ERA in Bruce Bochy's rotation, each of which were elevated marks compared to his 2011 campaign in which he posted a 2.71 ERA en route to his first All-Star appearance.

What's contributed to this increase in earned runs allowed? For starters, Vogelsong struck out nearly two less batters per nine innings in 2013 (5.8) than he did in 2011 (7.6). He also conceded nearly three more hits per nine last season (10.8) than two years ago (8.1), coupled with the fact that those hits went for extra bases more often in his latest campaign (.477 SLG%) than prior (.361 SLG%). However, it was Vogelsong's decrease in fastball velocity over the past two seasons that most contributed.

	Vel	MxVel	MnVel	League Vel Avg.
2013	89.1	92.5	81.1	91.3
2011	91.4	94.2	87.9	91

Comparing the velocity of Vogelsong's fastball between the two seasons, we see the pitch has regressed. In 2011 -- Vogelsong's best season as a professional (3.2 bWAR) -- the pitch's velocity ranged from 94.2 MPH to 87.9 MPH for an average of 91.4, which was slightly above the 91 MPH league average fastball velocity for starters. That average dipped to 89.1 MPH last season, however, and was more than two miles per hour slower than before while dipping below last season's league average fastball velocity mark of 91.3 MPH. What's important to understand is that this decrease in velocity has hampered Vogelsong's ability to attack right-handed hitters on the inside portion of the plate.

Batting average vs. Vogelsong's inner-half fastball, 2011

Batting average vs. Vogelsong's inner-half fastball, 2013

While Vogelsong's fastball velocity was only slightly above league average in 2011, he challenged right-handed batters with it by throwing it on the inner-half of the plate at a 39.3% clip, which was nearly five points higher than the 34.0% league average for southpaw fastballs against right-handed batters. And to his credit, he found success. Right-handers posted a .219 batting average against the offering in 2011 (excessively low for the .281 league mark) while placing 40.8% of those pitches in play (compared to the 44.1% league average).

As the second image indicates with clarity, opponents improved significantly against Vogelsong's fastball when located on the inner-half of the plate compared to two seasons ago. Challenging right-handers on the inner half at a 41% rate, elevated from 39.3% in 2011, Vogelsong's fastball was chewed up and spit out by right-handers, who garnered a .417 average (juxtaposed to the .276 league average) to go with a 53.7% in-play rate -- nearly 13% higher than in 2011 and well above the 46.7% league average mark.

Considering everything we've just discovered, what we're seeing is that A.) that Vogelsong's average fastball velocity is dwindling, and B.) that he should not longer challenge right-handed batters inside with the offering, due to the fact that opponents are making quality contact against it in that region. Locating it on the outer half of the plate, where he held righties to a .244 average last season, gives him a better chance to live up to his $5 million salary in 2014.

Comments

Vogelsong is right-handed.