Microtrends: Brad Brach's Splitter

With a mere eight games of Baltimore baseball in the books, we can't make too many concrete observations about the 2015 team. But we can certainly try, and looking at some of the smaller fluctuations — even those among relief pitchers — can give us ideas as to how the season might go. For Brad Brach, the early going might portend better results as the season progresses.

On the surface, Brach has struggled thus far, allowing five earned runs in his 4.2 innings of work. A .563 BABIP will distort any pitcher's results, though, and the peripherals tell a wholly different story: Brach owns a sparkling 2.18 xFIP, mainly because he's punched out six of the 23 batters he's faced. Compared to last year, in which he put up a strikeout rate of 21.2%, that represents a significant improvement, and it's come from one pitch in particular.

A couple months ago, my colleague Matt Kremnitzer noted some changes Brach made in his first Baltimore campaign:

Before this season, Brach had thrown his four-seamer the most, about two-thirds of the time, followed by his slider and splitter. But he threw his sinker 15% of the time last season, which took a chunk out of his four-seam offerings.

After relying heavily on a four-seam fastball for the first three years of his major-league tenure, Brach began to phase it out upon coming to the Orioles. So far in 2015, he's perpetuated that trend:

But he hasn't replaced those heaters with sinkers — his rate of the latter hasn't budged from last year. Rather, he's increased his usage of his splitter:

This has been something of a career-long trend for Brach: As he becomes more and more experienced, he leans more and more on his splitter. With a career SwStr% of 23.6% — well above the 15.5% baseline for the pitch — the pitch has always helped him rack up strikeouts, so throwing it more would certainly help with that.

It's fairly easy to see why Brach's splitter so befuddles batters. Its velocity has only increased:

League-average splitter velocity usually sits at 84 MPH, so 86 makes a sizable difference — one that has undoubtedly assisted Brach in fanning so many hitters.

In addition, Brach's splitter moves differently from most of its contemporaries. In 2014, the average splitter broke 4.5 inches to the right (from the catcher's perspective), and rose 2.5 inches. By contrast, Brach's splitter, since debuting in 2011, has shifted 9.3 inches horizontally, and 0.8 inches vertically. Together with the aforementioned velocity, this unconventional movement makes the splitter a legitimate force, and Brach appears to have finally realized it.

Of course, Brach probably won't stay this good for the whole season. Based on the fact that he walked 11.8% of the batters he faced prior to 2015, I'd say the 4.4% BB% he's posted thus far will regress a bit. Nevertheless, if he continues to utilize his splendid splitter as much as he has, he may progress further as a reliever. After the departure of Ryan Webb and the (early) struggles of Kevin Gausman, the Orioles could use that.

Has the 2015 season just begun? Yes. Will any earnest observations made now look preemptive come October? Probably. But that won't stop us from scrutinizing the inner workings of baseball, and doing what we can to separate the signal from the noise. And in the case of Brad Brach, the former appears to have a hand in what has occurred, and what will occur.

Investigating Wei-Yin Chen's Early Season Velocity

Wei-Yin Chen isn't a flamethrower. But he does throw slightly harder than the average major league starting pitcher. A pitcher's velocity certainly isn't everything, though it's worth keeping an eye on. And in his first start, Chen's fastball speeds were below his career averages and could possibly be an indication of the reversal of a recent trend.

Since entering the majors in 2012, Chen has an average velocity of 92.5 mph on his four-seam fastball and 91.9 mph with his sinker (or two-seam fastball). In 4-1/3 innings on Tuesday, Chen averaged 91 mph on his four-seamer and 90.1 mph on his sinker. By itself, that doesn't mean much; we're only talking about a few dozen pitches in his first appearance of 2015.

Let's take a look at Chen's average fastball velocities from April in his three previous seasons:

Date	FF	FT
Apr. '12	91.0	90.7
Apr. '13	92.0	90.5
Apr. '14	93.0	92.6

Chen has only ever pitched in three major league games where one of his fastballs averaged below 90 mph: on April 28, 2012; May 20, 2012; and April 26, 2013. So all occurred relatively early in the season.

In his first two seasons, Chen started out the year with lower fastball velocities. But that wasn't the case in 2014, and that improved velocity propelled Chen to his best season as a major leaguer. Chen has actually thrown his fastball harder every season in the majors (his age 26-28 seasons):

It's been nearly a decade since Chen had Tommy John surgery (in 2006), and he's throwing harder now than he has in a long time (and maybe ever). While pitching in Japan for the Chunichi Dragons, Chen's fastball velocity had actually been in decline before joining the Orioles:

2009: 90.7
2010: 90.2
2011: 88.8 (possible leg injury)

Pitchers usually don't see a consistent fastball velocity uptick in their late 20s. But whatever Chen has been doing now that he's in the majors has been working. Perhaps that includes a more disciplined workout regime, better coaching and guidance, and, except for an oblique injury in 2013, pretty good health (no arm injuries, at least).

Interestingly enough, Chen mostly throws fastballs, but he's starting to trade four-seamers for more sinkers:

He hasn't had to trade fastballs for more offspeed pitches; maybe that's something that will happen when he starts to lose velocity. But even if the gradual change in fastball usage hasn't had a dramatic effect, Chen's HR/9 dropped from 2012-2014 (1.35, to 1.12, to 1.11), and his flyball percentage has also dipped in the same span (42.1%, to 41.1%, to 37.5%). Chen's groundball percentage hasn't followed suit, exactly (37.1%, to 34.4%, to 41%), but last season was his career best in that department. Chen is not transforming into a groundball specialist or anything close to one, but it'll be intriguing to see what happens if he continues to opt for more sinkers.

Chen has previously demonstrated that a start or two with lower than average velocity (for him) doesn't mean bad things are necessarily on the horizon. But at some point his velocity is going to stop climbing and will level off and start to decline. As an impending free agent, Chen could be playing for another team before that becomes a real concern. But as the Orioles' lone lefty in the rotation, Chen bears a different kind of responsibility, and the O's would surely welcome a rebound effort in his next start.

Photo via Keith Allison

A Premature Look at O's Batters and Home Run Rates

The Orioles have a collection of hitters that really like to swing the bat. (Jonathan Schoop, for instance.) As a group, O's hitters are second in the majors in overall swing percentage (49.6%); they also chase 33.7% of pitches outside the strike zone (also second). Because of that lack of patience, they have a major league low walk rate of 6%. Overall, they are a middle-of-the-pack team in offensive production so far. They're 18th in runs scored, 18th in on-base percentage (.314), 14th in slugging percentage (.393), and 17th in wOBA (.312).

As you'd expect from a team trying to hit the ball out of the ballpark so often, the O's are fly ball heavy. Their 37.7 FB% is fourth in the majors. That by itself is not a problem; the 2013 Orioles, who tied for fifth in runs scored, had a 36.4 FB%. But last year's offense also had a home run to fly ball rate of 12.9%, which was the best in the majors. Right now, only 7.3% of the O's fly balls are leaving the ballpark (t-26th). And that has been an issue for an offense that relies on power (not OBP).

The Orioles mostly have the same cast of characters in the lineup this year. Obviously Nelson Cruz is a new addition and is crushing the ball. But Nick Markakis, Manny Machado, Adam Jones, Chris Davis, Matt Wieters, and J.J. Hardy are still here. They're all counted on to be regulars in the lineup. Machado only just returned from last season's serious knee injury last week; Hardy missed seven or eight games while battling a couple of nagging injuries; and Davis is currently on the disabled list with an oblique injury. Hardy and Machado have not hit well (obligatory small sample size reminder), and while Davis currently has a nice OBP (.372), he was not hitting for power before getting injured. But all of that can change very quickly with a few more fly balls turning into home runs instead of outs.

Here are the 2014 and career HR/FB rates for the main contributors to the O's lineup:

Player	2014	Career
Adam Jones	3.0%	14.7%
Chris Davis	10.0%	22.0%
Nick Markakis	4.8%	9.0%
J.J. Hardy	0.0%	11.2%
Matt Wieters	15.2%	11.9%
Nelson Cruz	25.7%	17.0%

Only Wieters (by a little) and Cruz (by a lot) are above their career averages. Hardy has yet to hit a home run. I did not include Machado, who has only played a few games. For what it's worth, he has a HR/FB rate of 8.7%. Jonathan Schoop is in his rookie year and has a career HR/FB rate of 11.1% in 112 plate appearances. It also might be interesting to look at guys like Ryan Flaherty, David Lough, Delmon Young, and Steve Pearce down the road depending on their roles or if they're still with the team.

Again, it's too early to draw many conclusions from the team's lower-than-expected HR/FB rate. According to Russell A. Carleton of Baseball Prospectus (and his handy table), HR/FB rate does not begin to stabilize until around 50 fly balls per batter. And we're not quite there yet. But this topic will certainly be worth revisiting later in the season, especially if the Orioles are still not scoring a ton of runs.

Really, the biggest help would be to get Davis back in the lineup and for the Markakis-Machado-Davis-Jones-Wieters-Cruz-Hardy group to stay healthy. Those seven have not played in a game together yet this season. Davis seems to be ahead of schedule, but last night Jeff Passan of Yahoo Sports reported that Wieters is experiencing elbow soreness and will be examined by Dr. James Andrews sometime this morning. Passan threw out the possibility of Wieters needing Tommy John surgery, which would obviously be devastating for the Orioles. But, for now, that's just speculation.

Stats (via FanGraphs) as of May 6, 2014. Photo: Keith Allison.