10 Degrees: April illusion or is Justin Verlander really losing zip on his fastball?

The scouts notice. Because it's April, and because his statistics are just fine, and especially because this is Justin Verlander they're talking about, they don't think all that much of it yet. That doesn't keep them from asking one another the same thing: Are you getting what I'm getting?

Four starts into the season, Verlander's fastball is AWOL. And the answer to their question is yes: Their radar-gun readings are not lying. The best fastball in baseball has simply been good.

"I've had him 91-93," said one AL scout who has seen two of Verlander's starts.

"He's been 90-94, topped out at 96," confirmed an NL scout.

PITCHf/x data captured around the major league parks verifies their readings. The data can be interpreted a number of ways. Baseball Info Solutions, which provides statistics for FanGraphs, says Verlander's average fastball this year is 91.9 mph. Brooks Baseball, which uses PITCHf/x for its proprietary data that usually is about a half-mile-per-hour faster, says it's 92.5 mph. Either way, the dip is precipitous compared to Verlander's recent past.

In April 2012, Verlander's average fastball was 93.8 mph, according to FanGraphs, making his 1.9-mph dip the third biggest in baseball this season. Scouts don't quite know what to make of it yet. Verlander long has been an anomaly. For other pitchers, they can wield their radar guns for the first inning or two of a start before holstering them as the game wanes. With Verlander, it's the opposite: He'll start a game off throwing in the low 90s before turning on some sort of superhuman turbo-booster whereby his fastball gets faster inning by inning.

By this time last year, he'd thrown 11 pitches in excess of 100 mph, including a 101.371-mph crackler in Kansas City. The speediest of his 267 four-seam fastballs this season, according to Brooks Baseball: 97.6 mph.

How far has Verlander's velocity dipped? PITCHf/x's algorithm automatically classifies pitches. It says 41.6 percent of Verlander's pitches this year are changeups. That's obviously wrong – Baseball Info Solutions says it's 18.7 percent – which means nearly a quarter of Verlander's fastballs are so far beneath his normal velocity that a computer is confusing them for an entirely different pitch.

This is not necessarily reason to plunge the panic button. Missing velocity notwithstanding, Verlander looks great. His strikeout rate is high, and his walk rate low. He has allowed one home run in 25 1/3 innings.

"He's still the best pitcher in baseball," the AL scout said.

Consider this more a keep-an-eye-on-him suggestion than a sky-is-falling proclamation. Drops in velocity are bad for obvious reasons. Balls are easier to hit. They portend injury. They correlate strongly with dips in effectiveness. And while he is an example so far this season …

1. Justin Verlander is far from the only pitcher whose fastball this year isn't where it was last year. Across baseball, there is about a 0.3-mph drop in fastball velocity compared to last April.

Which may represent a recalibration of the PITCHf/x cameras that capture velocity. Kansas City, where Verlander threw the 101-mph thunderbolt last April, has notoriously hot readings. As one AL executive noted: "There's so much context involved that only the pitcher and the team know about. Average velo is a data point, but there could be any number of other things going on. Frankly, in four starts, two of them could have been at parks with guns that were off or something. It's hard to get too worked up about any of those."

It's why few have panicked aloud about Verlander's missing velocity. Still, it's worth noting that research by FanGraphs' Jeff Zimmerman shows fastball velocity stabilizes around a pitcher's third start, which means the small sample size is not a hindrance in analyzing velocity. Indeed, last season, the gain in fastball velocity from April to the end of the season for starting pitchers was only 0.3 mph. Zimmerman's colleague Bill Petti, on the other hand, wrote that July may be the best month to worry about velocity. So we'll revisit this around the All-Star break, by which time …

2. Felix Hernandez hopes his fastball is still above 90 mph.

OK, that's an exaggeration. Not by much. King Felix's average fastball this year: an altogether plebeian 90.8 mph. It's only half a mile per hour less than last April, and Hernandez humped up to 92.1 mph for the season. That doesn't lessen any the steady drop his fastball has seen since he debuted with gas that threatened triple digits.

Perhaps better than anyone, Hernandez represents the fear teams have in giving huge money to pitchers: They're not Benjamin Button. Verlander just signed for $180 million in the aftermath of Felix getting $175 million. Zack Greinke, the $147 million free-agent prize this offseason, had an average fastball of 90.8 mph this April after sitting at 92.7 mph there last year. "I think he's evolving," one general manager said. "Less power, more pitcher."

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Zimmerman's research says from ages 26 to 37, average fastball velocity declines by 0.3 mph per year. Seeing as Hernandez's already took a Cousteau-quality dive, his evolution as a pitcher has been a work in progress and bodes well as long as the velocity doesn't portend an arm problem. Just now we're witnessing …

3. CC Sabathia reimagining himself on the fly. It's been an interesting April for the Yankees' ace, who has $99 million remaining on a four-year deal. Rather than cycle through the Five Stages of Grief, Sabathia let the Yankees do the denial part, skipped the anger, bargaining and depression, and went straight to acceptance that his once-mighty fastball was no longer.

"I'm hoping more velocity comes back," he said after his last start, "but if not, then we'll work with this."

Obvious already is this: Sabathia's drop – he's at 89.6 mph after 91.8 mph last April and a consistent 93-94 mph until last year – has made him, in the words of an NL scout, "a completely different pitcher." Sabathia, who used to pound right-handed hitters inside with fastballs and sliders, has spent far more time on the outer edge of the plate than before.

"I haven't seen him throw one back-foot slider to a righty," the scout said, and this heat map confirms Sabathia's reticence thus far to go inside with sliders.

One Yankees official says Sabathia's velocity will improve along with the weather. Maybe so. Or maybe, as Sabathia admitted, he'll have to do it with "smoke and mirrors." And that may not be the worst thing. Since a disastrous second inning on opening day against Boston, Sabathia has allowed just four earned runs in 26 innings against Detroit, Baltimore and Arizona, three stout lineups.

If that means a 6-foot-7, 300-pound finesse pitcher, well, there's another 6-foot-7 guy out west in …

4. Jered Weaver who's throwing slower than any right-handed, non-knuckleball pitcher has any business throwing. Let's put it this way: Knuckleballer R.A. Dickey's 82.2-mph fastball this year is only 3.3 mph slower than Weaver's heat.

On the disabled list with a broken left elbow, Weaver has time to build up his arm strength, because he's going to need it. After arriving in the big leagues with a 90-mph fastball and settling around 88-89, Weaver plummeted to 85.5 mph this season. Since PITCHf/x came into existence, only four right-handers have thrown slower: Greg Maddux, Livan Hernandez, John Burkett and Brian Lawrence. Perhaps Weaver can survive there. His delivery and release point flummoxed hitters at 88. What's a 3.1-mph drop from last year, the biggest from April to April?

A sign of small samples being misleading, he hopes. Because a drop that big screams injury, the same concern …

5. Chris Sale engenders in those who watch his violent motion and wonder when his body is going to give. It hasn't yet, though the fluctuations in his velocity may not be as stark as the numbers say.

Last April, Sale averaged 92.6 mph. This April, he's sitting at 91.3. Thing is, Sale lost more velocity from April 2012 to the end of the season than any pitcher in baseball – a full 1 mph. His last start was his best of the season, with his fastball topping out at 97 mph, and whether it was his arm tiring in his first full year last season or regular variance this year, maybe the real Chris Sale is more like 91.6 mph, which, for a left-hander, is more than acceptable. An 89.2-mph fastball, on the other hand, is just meh, and it's what …

6. Jonathan Niese is tossing this season after sitting at 91.1 mph last year. Granted, like Sale, Niese's velocity dropped as the season went on last year, finishing at 90.4 mph, but without a secondary pitch like Sale's slider, Niese's path to success is far more tortuous.

"Just didn't look the same this spring, and it's carrying over," one AL official said. "It's hard to maintain success when you are whiffing a guy every two innings."

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Niese's strikeout numbers are down to 4.9 per nine innings – small-sample alert is warranted here – but he's not exactly fooling hitters, either. Over his last two starts, Niese has generated just eight swinging strikes among 197 pitches. Not good. Not as bad as …

7. Ubaldo Jimenez morphing from the guy who could go 13-1 with a 1.15 ERA to start 2010 into someone who doesn't deserve a major league rotation spot.

PITCHf/x used to be Jimenez's friend. Since its introduction, the two seasons with highest average fastball velocity for a starter belonged not to Verlander, Stephen Strasburg or another hard thrower. They were Jimenez's, at 96.1 mph in 2009 and 2010. The next year, it dropped to 93.5 mph. Uh-oh. Last year lost another mph. And now it's at 90.9. Like Verlander, a majority of Jimenez's pitches are representing themselves as changeups.

Even if Jimenez can gain that half mph he got between April and September of last season, he's still a shell of what he was when he could paint corners with 100-mph sinkers. He's no longer even the hardest thrower in his rotation. That honor belongs to …

8. Justin Masterson and his 92.1-mph sinker – at least as long as Carlos Carrasco keeps throwing at people's heads and getting suspended. More important: Masterson is proof that velocity can crater in April and return to its normal levels soon thereafter.

Masterson's April 2012 velocity: 89.8 mph. He got back more than 2 mph during the season, so it's not like this 92.1 mph, is any surprise. Same goes for Anibal Sanchez, whose 1.2-mph April-over-April gain is more like a recovery from an awful month in 2012. And Madison Bumgarner, whose fastball disappeared during his rookie season only to regain 2 mph the next year and hold steady since.

Such cases, it must be noted, are rare. Almost always, when velocity goes, it stays gone. And if …

9. Roy Halladay took Sabathia's approach and accepted his body and arm for what they are, he might be better off than he's been. Yes, his last two starts brought his ERA back from the stratosphere. They didn't return the 1.5 mph that disappeared last year and the other 0.9 mph gone this year.

It's the same velocity David Price is down this year. Matt Moore (1.8 mph) and Mat Latos (1.5 mph) and Max Scherzer and Gio Gonzalez (1.3 mph) have lost even more. And yet it's Halladay whom an NL scout mentions when asked about velocity concerns.

"He lost his arm speed," the scout said, and for someone whose job is to notice such things, that's a damning appraisal. Nobody yet has said that about …

10. Justin Verlander, perhaps because even if he has permanently lost some sizzle on his fastball it's still better than 99 percent of what other pitchers offer. This is more a reminder: There is no such thing as infallibility in baseball.

A heavier-than-usual workload in Detroit's run to the World Series last season could have contributed. Same with a longer-than-usual spring training. Maybe it's nothing more than noise.

"There's not a checklist of things," the AL executive said. "It's more nuanced than that. You just know, from talking to trainers, pitching coach, etc., how a guy is feeling from day to day. It's pretty rare for a guy to actually feel 100 percent, so it's a matter of, is his back is a little sore, or does he have the bug going around the clubhouse, or was it a day game for a guy you know likes to go out?"

One typical excuse, weather, does not seem to apply. In Verlander's first four starts last season, the Fahrenheit temperatures were 43, 46, 64 and 50. In his starts this season: 35, 53, 65, 51.

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Ultimately, time will answer the question of whether the panic button deserves a tickle. While Verlander's fastball didn't return to its usual levels in his last start in Seattle, it was his best this season. And on Wednesday, when first-place Kansas City visits Detroit, the pitcher who more than any commands attention on the mound can't be insulted if he sees some eyes wander toward the left field.

They'll be looking at the scoreboard's radar-gun readings and hoping to see three digits for the first time this season.

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