How Much Will Ryan Vogelsong Regress?

Ryan Vogelsong wasn’t very good in 2010, when he pitched at triple-A for two different organizations (Angels and Phillies) and put up a combined ERA of 4.81 with a 1.8 K/BB ratio. It wasn’t as if he was even that good while pitching in Japan from 2007 through 2009 (4.17 ERA and a 2.6 K/BB rate in three seasons). His 2011 season was undeniably a brilliant one for fantasy GMs to take in, but doesn’t track record count for something?
When we look at some basic peripheral numbers, Vogelsong’s 2011 season looks fairly ordinary. His 2.28 K/BB rate was basically league average, as were his strikeout and walk rates. His swinging strike rate (7.2 percent) was over one percent below the league average (8.6 percent).

Though his BABIP against was low (.280), it wasn’t crazy low. He did, however, post a strand rate (or left on base percentage) of 80.4 percent, which was about eight percent above the league average. Given the lack of dominance in his numbers, he seems to have been a bit lucky in that department. In the end, there was a huge difference in his ERA (2.71) compared to most advanced pitching stats…

3.67 FIP
3.85 xFIP
3.97 SIERA
4.04 tERA
It wasn’t as if opposing hitters had a hard time making contact against Vogelsong and that contact became harder in the season’s second half. Below are the line-drive and home runs per nine rates against Vogelsong by month according to FanGraphs.
Month IP LD% HR/9
April 10.1 14.8% 0
May 35.1 17.8% 0.51
June 32 18.8% 1.13
July 31.1 21.0% 0.86
August 38 25.2% 0.71
September 32.2 20.2% 0.83
Looks like the league started to make an adjustment to Vogelsong the second time around.
If you are thinking that Ryan Vogelsong is going to put up another sub three ERA season, you are gravely mistaken. Both his track record and 2011 peripherals point to a big regression in terms of ERA and WHIP in 2012. Don’t be surprised if his ERA is closer to four and WHIP closer to 1.35. He won’t be taking the league by storm next season, don’t let him take your fantasy team down the standings by overvaluing his skills on draft day.