Jake Arrieta: luck, BABIP, LOB%, and more

[Jordan Tuwiner]

I'm not going to deny it: Jake Arrieta has been extremely inconsistent this year. His last few starts have been terrible and many are pushing for him to lose his rotation spot.

While looking at Arrieta's ERA and the amount of ERs he gives up in each start, it's easy to see why people are getting tired of watching him pitch.

But looking a bit deeper into his stats, Arrieta has actually improved as the season has gone on even if his ERA may not show it.



He struck out more batters and walked slightly less, which led to a lower FIP and xFIP. His HR/9 jumped a bit, but that was due to his increase in HR/FB%. He also got a bunch more ground balls in May.

What sticks out on the chart is his .133 jump in BABIP. That's obviously one of the biggest factors for his high ERA.

Some of you now may be wondering why Arrieta's ERA was still fairly high (4.45) in March/April. A lot of that has to do with his LOB%, which was 59.9% in Mar/April (only 59% for the season). His career LOB% is 69.0%.

Arrieta's career BABIP is .023 points lower than his 2012 BABIP, and his 2012 LOB% is nearly 10% lower than his career LOB%. Arrieta is showing signs of improvement in nearly every area of his game this season, he's just been a bit unlucky lately.

I'm not concerned with Arrieta. I still feel his bad luck will normalize and when it does, his combination of stuff, strikeouts, and fairly low walk rate will turn him into at least the mid-rotation starter the Orioles are looking for.

[OriolesRedskins28]

Wow great post, it really puts a different perspective on Arrieta's season when the details are presented in that fashion.

His start today was pretty bad though. The stretches he goes through where he can't find the zone against 8 and 9 hitters is disturbing. Hopefully he is able to iron out his mechanics and sharpen his mental focus to improve his consistency.

[Matt P]

Bottom of the 4th - Walk, single to center, wild pitch advances both runners, sac fly scores 1 run and then another scores on a bad throw by Jones BUT that run would not have scored if Arrieta backed up 3rd base (Palmer seemed amazed he wasn't backing up the throw in the booth), ground out, foul out.

Bottom of the 5th - Fly out, walk, walk, fielders choice, walk, double that scores 2, and he is relieved.

None of the 4 runs he gave up today were due to luck or anything of the sort. Both hits were legitimate hits as neither were bloopers, a misplay by a fielder, etc. He struck out 3 in 4.2 so I can't imagine it hurts his overall K/9 much. I'm probably in the minority but those stats don't make me change my mind on what I see every time he pitches.

The first 3 innings he looked amazing and then he fell apart which he seems to always do. He's just inconsistent and shouldn't be in a major league rotation until he figures it out.

[Rising O's]

Seems more mental than mechanical with how he looks on the mound.

[Jordan Tuwiner]

Bottom of the 4th - Walk, single to center, wild pitch advances both runners, sac fly scores 1 run and then another scores on a bad throw by Jones BUT that run would not have scored if Arrieta backed up 3rd base (Palmer seemed amazed he wasn't backing up the throw in the booth), ground out, foul out.

Bottom of the 5th - Fly out, walk, walk, fielders choice, walk, double that scores 2, and he is relieved.

None of the 4 runs he gave up today were due to luck or anything of the sort. Both hits were legitimate hits as neither were bloopers, a misplay by a fielder, etc. He struck out 3 in 4.2 so I can't imagine it hurts his overall K/9 much. I'm probably in the minority but those stats don't make me change my mind on what I see every time he pitches.

The first 3 innings he looked amazing and then he fell apart which he seems to always do. He's just inconsistent and shouldn't be in a major league rotation until he figures it out.

Yes, of course. Today was a different story.

In general though, a lot of it has had to do with luck. Going to the minors really isn't going to fix anything for him, and I don't think moving to the bullpen would either. They don't have any better options and letting Arrieta's luck normalize -- or for him to figure things out, if that's what you believe -- in the rotation would be best.

[Matt P]

Look at his last start against Toronto.

1st and 2nd are 3 up 3 down innings.

3rd - Two singles to center, a bunt single that Arrieta made a throwing error on a ball he should have let his 3B make a play on, strike out, ground out scores a run, fly out. The bunt single was a great bunt by a fast player but it should have had the bases loaded with nobody out instead of 2nd and 3rd with 1 run scored and nobody out.

4th - Ground out, ground rule double, walk, double that scores 2 runs, error by Jones, single that scores a run, strike out, line out. There is nothing unlucky involved in giving up two doubles, a walk, and a single. The error costs him some pitches but if memory serves it didn't factor into any runs scored.

5th - Walk, walk, strike out, taken out of game and the two batters he walked scored. You can blame it on the reliever but he put the men on base by walking them.

The start before that against Boston also had very little luck involved with the runs they scored off of him.

[Shorebirdfan]

Mark Twain coined the phrase, "There are lies, dam lies and statistics.'

This is a great example of that. I know what I've seen and little about Arieta has improved.

[CSPitt17130]

Mark Twain coined the phrase, "There are lies, dam lies and statistics.'

This is a great example of that. I know what I've seen and little about Arieta has improved.

The statistics don't lie. It's the people who choose to frame them in one way or another that lie. In this case, Jordan is using statistics in the way that the smartest people in baseball widely accept as a smarter way to look at pitchers than things like W/L record and ERA.

Arrieta's Ks and BBs haven't just improved from April to May, but they have improved significantly from 2011, yet his ERA is about a half run higher in 2012 than it was in 2011.

[A_K]

It's a special kind of ignorance that is presented with a contrary perspective and instead of considering the alternative view, calmly reiterates its previously held position without remorse. Evidence is irrelevant, apparently.

Nice post, Jordan. Well demonstrated.

[CSPitt17130]

The start before that against Boston also had very little luck involved with the runs they scored off of him.

If by luck, you mean a ground ball bouncing off a base or taking a bad hop that led to runs, that's not the kind of luck that's relevant here. Read an explanation of BABIP.

[Matt P]

The reason his stats are good is because he is dominant for multiple innings. The reason his ERA is bad is because he is horrible for an inning or two. Nobody mentioned W/L at all.

[CSPitt17130]

I was going to post Voros McCracken's article again, but I found this video from a Fangraphs writer and thought that it might be better.

http://www.youtube.com/watch?feature=player_embedded&v=M8XEZlfwCT4#!

[Ampontan]

The start before that against Boston also had very little luck involved with the runs they scored off of him.

If by luck, you mean a ground ball bouncing off a base or taking a bad hop that led to runs, that's not the kind of luck that's relevant here. Read an explanation of BABIP.

The use of the word "luck" in this context by statheads is an unfortunate choice. What they really mean is a statistical anomaly---the stats they like to use say he should be doing better, but he isn't.

While I am not opposed to the use of modern statistical methods, particularly for front office evaluators, as a fan, the older I get, the more interested I become in just one statistic: Is the pitcher successful at keeping runs from scoring?

Right now, Jake isn't successful.

[Jordan Tuwiner]

The start before that against Boston also had very little luck involved with the runs they scored off of him.

If by luck, you mean a ground ball bouncing off a base or taking a bad hop that led to runs, that's not the kind of luck that's relevant here. Read an explanation of BABIP.

The use of the word "luck" in this context by statheads is an unfortunate choice. What they really mean is a statistical anomaly---the stats they like to use say he should be doing better, but he isn't.

While I am not opposed to the use of modern statistical methods, particularly for front office evaluators, as a fan, the older I get, the more interested I become in just one statistic: Is the pitcher successful at keeping runs from scoring?

Right now, Jake isn't successful.

I'm not arguing that he's been succesful. The point I'm trying to make is that pitchers with his combination of strikeouts, walks, BABIP, etc., usually become more succesful if they are performing as bad as Jake has. His stretch of rough outings should with the numbers he's putting up.

[Matt P]

It looks like his next 2 starts are against the Philles and Pirates. In terms of scoring the Phillies have been average and the Pirates have been the worst in baseball. Let's hope he can turn it around against these two teams.