Is It Legit? Blake Treinen's Breakout Season

We're back with another edition of "Is It Legit?" to discuss another surprising breakout performer from the 2018 MLB season in order to assess his value heading into 2019.

With so many players seemingly becoming fantasy baseball darlings overnight, it can be challenging to sift through the multiple hype trains and determine which players are actually expected to produce similar, or even better, numbers the following year.

Oakland Athletics closer Blake Treinen had a season for the ages in 2018, recording 38 saves with an outstanding 0.78 ERA and a 0.83 WHIP. Was his tremendous season legit or will we see some major regression for the flame-thrower in 2019?

Is Treinen's Stuff That Filthy?

Treinen's 2018 numbers are staggering to look at. He threw 80 1/3 innings with a 100/21 K/BB ratio and just seven earned runs allowed. His 0.78 ERA is one of the best of the last decade, and his 0.83 WHIP isn't too shabby either.

It was unexpected, to say the least, to see Treinen break out on this type of level. He had thrown between 67 and 75 innings in each of the last three years, with a FIP between 3.42 and 3.62 and a K/9 hovering around 8.75. He was a consistently average middle reliever with command issues and electric stuff who seemed destined to never quite put it together, until he did.

Treinen's 11.20 K/9 was 2.4 K's higher than 2017, thanks to a 42.1% o-swing rate, which is the rate that hitters swung at pitches out of the strike zone. That was an 11% jump from 2017. Hitters weren't only chasing more, but they were missing more, with an 18.0% overall swinging strike rate - a five percent increase from 2017. Basically, Treinen went from posting average swing-and-miss stuff to elite.

He's always had the stuff to strike hitters out, possessing a 99 MPH sinker with a ton of movement and a 90 MPH slider that drops off the face of the Earth. However, hitters were able to find ways to make contact in previous years, likely thanks to poor location, either in the middle of the strike zone or way off the plate thanks to a lack of command.

His command underwent the biggest change, as Treinen lowered his walk rate steadily in each of the last four seasons: from 4.35 BB/9 in 2015 to 4.16, then to 2.97 and finally 2.35 in 2018. A pitcher with his arsenal who can command it instantly becomes nearly impossible to deal with; that is what happened last year.

Is a Repeat Possible?

Now - is it sustainable? Obviously, a 0.78 ERA is pretty unlikely to be repeated. Indeed, Treinen did get away with a .230 BABIP and an 85.9% LOB rate - which does point to some luck on his side. His FIP was 1.82 and his SIERA was 2.46, a likely indicator of what his actual performance level should have been.

Still - it's hard to argue with an ERA in the mid-2.00s, especially with strikeout rates over 10 K/9. And frankly, there's not any reason Treinen can't post similar numbers again in 2019. He still pitches in a huge pitcher's park, his command appears to be sustainable after a four-year downward trend in walks, and his stuff is still unhittable when located well.

His number of saves will be dependent on how Oakland performs, but no one will challenge him for the closing role, so he has a great chance of posting 30+ saves with elite strikeout rates and above-average ratios next season. That automatically makes him a top-five closer in all fantasy formats, and he should be drafted as such.

He won't post an ERA under 1.00 next season, but he should still be treated as a top-tier closer heading into 2019 drafts.

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