Comparing April Velocites to April 2012 Velocities

Last week I looked at early season velocity gainers and losers. It was noted that the average fastball velocity so far is down league wide from where it was in 2012 but fairly consistent with the average fastball velocity in April 2012. But some commenters suggested that it might be useful to look at the April 2012 velocities of the guys who have seen the biggest gains and losses in velocity this year. The idea is to see if the discrepancy between 2012 velocities and April 2013 velocities is an indication of a change or just evidence that a guy tends to see his velocity dip or rise at the beginning of the year.

To gather a sample, I created a list of guys who threw 150+ innings last year and who had at least 20 innings this April. That yielded me a list of 70 pitchers. To find the significant changes in velocity, I calculated the differences in average fastball velocity between all of 2012 and April 2013. I then calculated the average difference and standard deviation to see who had made the biggest changes. Below are the guys who saw the biggest gains in velocity in April.

	2012 Total		2013 April
Name	FB%	FBv	FB%	FBv	2012 to April 2013 Gap
Dan Haren	40.10%	88.5	46.50%	89.5	1
Mike Leake	46.30%	89.6	53.50%	90.3	0.7
Ian Kennedy	65.90%	89.7	64.00%	90.2	0.5
Jason Vargas	57.10%	88	54.70%	88.4	0.4
Homer Bailey	61.60%	92.5	64.30%	92.9	0.4
Josh Beckett	48.00%	91.4	43.60%	91.7	0.3
Derek Holland	68.50%	93	52.80%	93.3	0.3
Yu Darvish	47.30%	92.8	34.20%	93	0.2

 

Then I calculated the differences between average fastball velocity in April 2012 and April 2013 to see who has started this year out differently.

	2012 April		2013 April
Name	FB%	FBv	FB%	FBv	April 2012 to April 2013 Gap
Dan Haren	43.10%	88.8	46.50%	89.5	0.7
Mike Leake	36.20%	89.6	53.50%	90.3	0.7
Ian Kennedy	61.20%	89.6	64.00%	90.2	0.6
Jason Vargas	55.50%	87.7	54.70%	88.4	0.7
Homer Bailey	67.10%	92.5	64.30%	92.9	0.4
Josh Beckett	49.70%	91.4	43.60%	91.7	0.3
Derek Holland	63.50%	93.1	52.80%	93.3	0.2
Yu Darvish	51.60%	92.9	34.20%	93	0.1

 

These all appear to be significant changes in velocity as opposed to just being a list of guys who tend to see their velocities rise as the temperatures and their arms warm up. But it’s worth noting that these increases in velocity haven’t necessarily led to increases in performance. In fact, the four who have seen the biggest gains from April to April (Haren, Kennedy, Vargas and Leake) currently have a K%-BB% that is lower than what they posted in 2012 and a SIERA that is higher than what they posted in 2012. The main problem for Kennedy, Vargas, and Leake has been an increase in walks that has come along with the increase in velocity.

But walks have gone down for Haren. Unfortunately, it would appear that living in the zone so much to bring the walks down has led to him allowing more homers. His Zone% is way up from where it has been the last three years and is 3.6% higher than his career average. Hitters are also swinging less at pitches outside the zone, more at pitches in the zone, and making more contact on pitches in the zone. It would not appear that the increase in velocity is leading to a Haren resurgence.

As for the other four who have seen their K%-BB% and SIERA improve so far this season, Holland, Bailey and Darvish have also seen an improvement in ERA.

But Josh Beckett is carrying a 5.24 ERA (3.95 SIERA). The increase in velocity has led to a jump in strikeouts and swinging strikes, and it hasn’t been accompanied by a jump in walks. But Beckett has had the same problem Haren has had, home runs. However, Beckett’s home runs may be more bad luck than his fault. His Zone% is 3.4% lower than his career average, he’s generating more swings and misses, and he’s giving up less contact on pitches in the zone. If there’s a “buy-low” target to come out of this, it’s Beckett.

What about the velocity losers? Below are the guys who saw the biggest losses in April compared to all of 2012 along with the difference between their April 2012 and April 2013 velocities.

	2012 Total		2013 April			2012 April
Name	FB%	FBv	FB%	FBv	2012 to April 2013 Gap	FB%	FBv	April 2012 to April 2013 Gap
Hiroki Kuroda	50.40%	91.8	48.00%	90.5	-1.3	55.00%	91	-0.5
James McDonald	62.30%	91.8	61.10%	90.5	-1.3	61.00%	91.3	-0.8
Jeremy Hellickson	52.40%	91.4	48.60%	89.9	-1.5	53.90%	90.6	-0.7
Mat Latos	58.50%	92.6	62.50%	91.1	-1.5	61.20%	92.6	-1.5
Tommy Hanson	55.10%	89.7	47.40%	88.2	-1.5	56.80%	89.8	-1.6
Cliff Lee	54.30%	91.7	60.80%	90.1	-1.6	48.60%	90.8	-0.7
Max Scherzer	60.80%	94.2	57.00%	92.6	-1.6	62.70%	93.7	-1.1
R.A. Dickey	14.00%	83.4	8.50%	81.8	-1.6	15.50%	82.9	-1.1
Matt Moore	65.90%	94.4	63.50%	92.6	-1.8	72.50%	94	-1.4
David Price	60.70%	95.5	56.90%	93.6	-1.9	59.80%	94.6	-1
Justin Verlander	55.90%	94.3	57.60%	92.1	-2.2	56.90%	93.8	-1.7
Felix Doubront	63.50%	92.7	64.40%	90.4	-2.3	65.20%	92.3	-1.9
CC Sabathia	54.00%	92.3	58.20%	89.8	-2.5	57.00%	91.8	-2

Once again, all of the losses appear to be real. It doesn’t seem to be a case of guys being slow starters. And some of them have lost a substantial amount of velocity with those whose April-to-April difference is more than one standard deviation below the mean being bolded and those whose difference is more than two standard deviations below the mean in italics.

A drop in velocity isn’t always a bad thing. For Latos and Scherzer, the decrease in velocity has come along with an increase in control. Latos’ BB% is 5.1% compared to 7.5% for his career. And Scherzer’s BB% is down to 5.5% compared to 7.9% for his career and 7.6% last year.

Max Scherzer really stands out because so many of his other numbers have improved, although they’re not necessarily a result of the change in velocity. His SwStr% is way up to 13.6%. His first pitch strike percentage is up. He’s inducing  swings on pitches outside the zone at a clip much higher than he ever has before. Perhaps most importantly, Scherzer’s line drive rate is 16.9% (20.4% career). Hard contact has always been Scherzer’s bugaboo, but he has limited the line drives and homers so far this year. All of this has led to a 2.05 SIERA. Why the 4.02 ERA? The .380 BABIP and 64.3% strand rate are the obvious culprits. Scherzer is also a nice “buy low” option.

What about sell high candidates? Dickey, Sabathia and Hanson are the pitchers who have seen diminished strikeout and walks skills with the lesser velocity. Let’s throw Dickey out because a) the fastball isn’t his main pitch, and 2) he hasn’t been good so you can’t really sell high. As for Hanson, if you can get anything of value for him, do it. But I doubt many people are trading for Hanson at this point.

CC Sabathia is the real scare here. His strikeout rate is down, his swinging strike rate is down, and he’s inducing significantly less swings on pitches outside the zone.  He’s also giving up more than a home run per nine innings, which is something he hasn’t done in any of his 12 previous seasons. Like Haren, it might be his fault. He’s living in the zone more than he has in years. His first pitch strike percentage is 4.6% higher than his career average. His Zone% is the highest it has been since 2008. He doesn’t appear to be in danger of falling off the map, but he may not be the stud that he used to be.