Can Mat Latos Regain His Velocity?

Mat Latos began and ended his 2014 season by missing time because of injuries. Between the two layoffs, he seemed to produce like he did in the past with a 3.25 ERA (3.34 for his career). One difference between his previous couple of seasons and 2014 was a huge drop in strikeouts. They went from 8.0 K/9 in both 2012 and 2013 to 6.5 K/9 in 2014. The biggest reason for the decline in strikeouts was a near 2 mph drop in his fastball velocity. This off season he was traded from the Reds to the Marlins where he hopes regain some of the zip on his fastball, but I wouldn’t count on it.

On average, pitchers lose some velocity every season with the amount of decline  starting to really increase from the age 26 to 27 season.

Latos’s drop happened right before this age range, but the decline is on average a quarter to a third of a mile per hour. Not the nearly 2 mph decline Latos saw.

So should we expect much of a rebound with Latos’s velocity? If so how much? I examined data from 2005 to 2014 for when a starter threw a minimum of 10 IP (fastball velocity stabilizes quickly) and started at least half their games for three consecutive seasons. I did the same for relievers (half of their appearances were in relief each season). Here is how the data broke down.

Note: I included median values because I wanted to make sure a few large values didn’t dominate the average change.

Starters

MPH change	Average change (Y1 to Y2)	Median Change (Y1 to Y2)	Average change (Y2 to Y3)	Median Change (Y2 to Y3)
+1 or more	1.6	1.5	-0.4	-0.5
+0.5 to +0.9	0.7	0.6	-0.8	-0.1
+0.4 to -0.4	0.0	0.0	-0.2	-0.3
-0.5 to -0.9	-0.7	-0.7	-0.2	-0.2
-1.0 to -1.4	-1.1	-1.1	-0.1	-0.1
-1.5 to -1.9	-1.6	-1.6	-0.3	-0.4
-2 or less	-2.3	-2.3	0.6	0.4

Relievers

MPH change	Average change (Y1 to Y2)	Median Change (Y1 to Y2)	Average change (Y2 to Y3)	Median Change (Y2 to Y3)
+2 or more	2.4	2.3	-0.3	-0.3
+1.5 to +1.9	1.7	1.7	-0.6	-0.4
+1 to +1.4	1.2	1.2	-0.5	-0.4
+0.5 to +0.9	0.7	0.6	-0.4	-0.3
+0.4 to -0.4	0.0	0.0	-0.3	-0.3
-0.5 to -0.9	-0.7	-0.7	-0.5	-0.1
-1.0 to -1.4	-1.2	-1.2	-0.1	0.0
-1.5 to -1.9	-1.7	-1.7	0.1	0.1
-2 or less	-2.4	-2.3	0.8	0.5

Well a huge bounce back doesn’t look likely, but his velocity change (officially -1.9 mph) falls right at the difference between the last two ranges. Looking at the starters who saw -1.7 mph to -2.1 mph change here are the results:

Category	Value
Average change (Y1 to Y2)	-1.9
Median Change (Y1 to Y2)	-1.8
Average change (Y2 to Y3)	0.0
Median Change (Y2 to Y3)	-0.2
% Increase	48%
Largest Increase	1.5 mph
% Decrease	52%
Largest Decrease	-1.7 mph

The future doesn’t look bright for Latos. The “good” news is his velocity will likely not decline any further in 2015, but neither will it go up. Looking at the 97 pitchers who lost between 1.0 and 1.4 mph, 11% gained 1 or more mile per hour after the loss. On the other hand, 16% lost an additional 1 mph or more.

Don’t ever assume a pitcher will regain lost velocity after experiencing significant decline. The best case estimate is the pitcher will stay constant. If Mat Latos see’s a large bump up, great, but he will be the exception instead of the rule.