Odds of Regaining Velocity, by Age

A number of pitchers with noticeably lower velocity this year either have landed on the disabled list or have had their seasons cut short due to injury. The Pirates’ Charlie Morton had Tommy John surgery (age 28, down 1.5 mph). The Tigers’ Doug Fister (age 28, down 1.1 mph) and the Blue Jays’ Brandon Morrow (age 27, down 1 mph) have both landed on the DL with oblique injuries. And the White Sox’ John Danks (age 27, down 1.5 mph) just started a stint on the DL due to elbow soreness.

Previously, I found that pitchers who lose at least 1 mph of velocity have over twice the odds of not throwing at least 40 innings in the subsequent year. This could simply be due to ineffectiveness, injury or both. A steep decline in velocity can create — or be a signal for — all sorts of problems. If a pitcher loses velocity simply due to a tired arm, they can increase their chance for injury by trying to pitch through it. Losing velocity also tends to make pitchers less effective over time. And once a pitcher loses velocity, the odds of regaining at least some of it the following year are very low (more on this below).

Today, I want to look at how age impacts the chances of regaining velocity for pitchers and then highlight some hurlers who fans should keep their eyes on this year and next year.

Once again, I looked at pitchers from 2002 to 2011 who pitched in three consecutive years and maintained the same role (i.e. starter or reliever) in each season.

Since the N-sizes started to get pretty small once I segmented the data by age,  I’m only reporting results for pitchers from ages 24 to 33. Below we see the percent of pitchers who gained velocity in the season following a velocity decline of 1 mph or more. I also included the odds ratios for each age cohort — that is, the increase or decrease in likelihood that a pitcher will gain velocity the following year, compared to those who did not lose 1 mph or more the previous season. For example, at age 24, pitchers who lost more than 1 mph had only .24 times the odds of gaining velocity the next year relative to 24-year-old pitchers who didn’t lose 1 mph or more the previous season.

Age	% Gain Velocity	Odds Ratio	Ave Velocity Gain (mph)	Ave Velocity Loss (mph)
24	14%	0.24	0.9	-1.7
25	19%	0.30	0.4	-1.6
26	5%	0.10	0.7	-1.3
27	13%	0.25	0.3	-2.0
28	5%	0.12	0.5	-1.6
29	0%	0.00	0.0	-1.7
30	10%	0.22	0.4	-1.4
31	0%	0.00	0.0	-1.7
32	8%	0.23	0.1	-1.3
33	0%	0.00	0.0	-1.5
All	7%	0.16	0.4	-1.6

Not surprisingly, the odds of regaining any of the lost velocity are generally quite low, regardless of age (7%, odds ratio for all pitchers of .16). However, we do see some difference by age, and the odds ratios are statistically significant at the .01 level. We also see that, while some pitchers can gain back some velocity after suffering a loss, the gain is quite small and, on average, doesn’t get them back to where they were the previous season. Additionally, as most pitchers decline the following year, we see that the declines are quite large. In many cases, the declines average more than the initial drop.

Given this data, who are some pitchers this year who we might want to keep our eyes on?

Jaime Garcia (age 25), RHP, Cardinals

After two solid years as a starting pitcher for St. Louis, Garcia is now on the disabled list with a shoulder injury. He hopes to avoid surgery but it’s unclear at this time what will happen. Garcia lost roughly 1.5 mph off of his fastball from 2011, though as a 25-year-old, his odds of recovering some velocity are actually the best of any age cohort (19%, .30 odds ratio). Still, the velocity decline isn’t simply a factor of being tired, as the shoulder injury shows. Twenty-five-year-olds averaged another 1.6 mph velocity decline the next year, so there’s a risk that Garcia could find his fastball dipping into the 86.5 mph to 87 mph range in 2013.

Tommy Hanson, (age 25), RHP, Braves

After a shoulder injury cost him more than 1 mph on his fastball and limited him to 22 starts in 2011, Hanson has continued to show signs of decline in Atlanta. So far this year, Hanson has seen his strikeout percentage drop 6% and his fastball velocity drop another 1.4 mph. Amazingly, Hanson’s ERA- is actually better this year, but this appears due largely to the fact that more than 80% of his runners have been left on base. As with Garcia, there’s some hope that Hanson can regain some velocity — but he’s been trending down since 2010.

Jonny Venters (age 27), LHP, Braves

Atlanta needs to be careful how its handles Venters the rest of this season. After two straight excellent years out of the bullpen, the left-hander has lost a 1 mph on his fastball (which still sits at 94 mph) and hasn’t been as dominant. His strikeout and walk rates are in line with his career numbers, but his home run rate jumped and he’s already given up more home runs this year than in in the previous two years, combined. When batters aren’t striking out, they’re hitting the ball hard. Venters appeared in 79 games in 2010 and another 85 last year. That’s a lot of work in two years, especially considering that he’s on pace to appear in a similar number of games this year. The Braves rode their bullpen hard last year, and it might be Venters who ultimately suffers.

Ricky Romero (age 27), RHP, Blue Jays

A lot of people (including myself) picked Toronto to be a breakout team this year. The big caveat was its pitching. If the young rotation could take the next step in their development, they’d have a chance to challenge for one of the American League’s Wild Card spots. But Brandon Morrow has already landed on the DL, Kyle Drabek just followed him and Henderson Alvarez hasn’t been nearly as good as last year. And then there’s Romero.

The 27-year-old posted an 71 ERA- last year, despite a 103 FIP-. This year, Romero’s strikeout rate is down 2%, his walk rate is up 3% and his HR/FB ratio is up 2%. Not surprisingly, his ERA- is now a tick above league average. Romero also has lost a full 1 mph off his fastball. Twenty-seven-year-olds have the third-highest rate of regaining velocity (13%) and the second-highest odds ratio (.25), so there’s some hope here. Still, the average gain is only .3 mph, and the average loss is the highest of any age group (2 mph). With his performance looking more like his peripherals predict, Romero’s velocity decline doesn’t bode well for him this season, or next.

Tim Lincecum (age 28), RHP, Giants

It would be impossible to talk about pitchers with lower velocities and not bring up Lincecum. The two-time Cy Young Award winner is easily having the worst season of his career. While Lincecum’s peripherals look similar to his career numbers (outside of a jump in walks), he has a 155 ERA-. Lincecum entered the league as a flame-throwing righty, but he’s seen is velocity steadily decline. Lincecum did manage to regain about 1 mph last year — which was much higher than the average 27-year-old who loses 1 mph (.3 mph). But Lincecum is currently sitting 2 mph lower than last year.

Combine that decline with the fact that, since 2002, only one 28-year-old out of 25 has managed to regain any velocity after a drop and the future does not look bright for San Francisco’s right-hander.

Jonathan Papelbon (age 31), RHP, Phillies

Philadelphia made a big offseason splash after signing Papelbon, who arguably had been the best closer not named Mariano Rivera. The Phillies committed $50 million over the next four years to the former Boston closer. The move certainly generated some criticism, given the large amount of money and the coming needs of the Phillies aging roster. Phillies fans should also be concerned at Papelbon’s velocity loss this year. In 2011, Papelbon averaged 95 mph on his fastball. So far in 2011, it’s dropper to 93.4 mph. Papelbon is 31 yearsold and the track record for these types of pitchers is not encouraging.

Since 2002, not one 31 year-old pitcher who has lost at least 1 mph managed to regain any velocity the following year. In fact, none of those 18 pitchers even managed to hold steady. All 18 lost additional velocity the following year, averaging 1.7 mph less on their fastball in their age-32 season. Papelbon has been quite good this year, but he’s already seen his strikeout percentage drop more than 4%.

Keep in mind that many pitchers do gain velocity as the season wears on — as some of the velocity charts suggest. It’s possible that some of these pitchers could erase their velocity decline by the year’s end. But if they don’t, fans and front offices should temper their expectations for a rebound in 2013.