Sorting out the Oakland A’s bullpen

Entering the season, the 2019 Athletics looked very similar to the 2018 team. The offense, defense and bullpen all figured to be very good, if not elite. The starting rotation was supposed to be the team’s only question mark.

So far, the rotation has been just as inconsistent as we all expected. But the bullpen has disappointed. The relievers were fully responsible for 5 of the A’s first 10 losses, and at least partially responsible for a few others. And the struggles haven’t been isolated — almost every arm in the A’s ‘pen has contributed in some way.

How can they turn it around? Let’s take a look at each player and fix this bullpen.

Blake Treinen and Lou Trivino

We’ll start with the easy ones. Blake Treinen and Lou Trivino are easily Oakland’s best relievers, and arguably two of the best relief arms in the game. They’ve been very reliable for the A’s in the early going.

Each has had a bad outing or two, but nothing to be overly concerned about. If anything, Treinen has been more wild than we’ve seen in years past. His 15.2% walk rate is way up from his 6.7% mark in 2018. But the righty has still been dominant, thanks to a small uptick in strikeout rate, and I’m confident he’ll turn it around. After all, he’s only thrown 11.1 innings — we’re talking about a difference of just a couple walks for now.

For these two, the trick will be managing workload. In 2018, Trivino threw his most innings since 2015, while Treinen threw his most since 2014. Trivino in particular seemed to hit a wall late in the season, while Treinen looked gassed in the Wild Card game. Both are former starters, but that was half a decade ago and before they consistently threw 100 MPH. The A’s can’t use these two every day.

On Sunday, Bob Melvin chose not to go to Trivino with a three-run lead and then quickly saw that lead evaporate. This decision came after an off-day due to a rainout and before another scheduled off-day, but after a stretch of 16 consecutive games. Theoretically, the A’s should have been able to win that game without Trivino and/or Treinen. But if the rest of the bullpen continues to struggle, Melvin may need to lean harder on his relief aces — and indeed, he got eight outs from them on Wednesday against the Astros.

Joakim Soria

The A’s largest free agent addition last offseason, Joakim Soria was expected to replace Jeurys Familia in a set-up role. The righty is almost 35, but was coming off two consecutive dominant seasons and should have been a safe signing.

But 21 games into the 2019 season, he hasn’t looked great. Soria has a 9.72 ERA and was solely responsible for Sunday’s loss. His walk and hard hit rates are up, while his strikeout, ground ball and strand rates are down. Soria has been ineffective, to say the least.

But these struggles come with one major caveat — it’s way too early. Soria has only thrown 8.1 innings. He is still averaging 92-93 MPH with his fastball, right around where he’s been for most of his career. Even with his rate stats all out of whack, he still has a 3.62 FIP. He’s only given up runs in three games this year, and been good seven times, so it’s not like he’s been a lost cause every time out. It’s just that the blowups have been both extreme and costly.

I think Soria will be fine. He has a lengthy track record of success, and a couple bad weeks doesn’t erase that. But the pressure is on. He is a crucial late-inning piece, and a lot of this bullpen’s success will hinge on his performance.

J.B. Wendelken

After a strong finish to the 2018 season that saw him earn a spot on the playoff roster, J.B. Wendelken was dominant to begin 2019. Alex and Joseph both wrote about his breakout potential, and while the righty has taken a step back in the past week or so, he remains a key bullpen piece.

Wendelken is the last of the four A’s relievers I would trust in a save situation. This makes him a pivotal arm. The A’s won’t have a strong season if only Treinen, Trivino and Soria can be trusted with a lead. They will need at least four reliable arms, and Wendelken has the best chance of being that fourth guy.

Fortunately, he is very good. While it isn’t realistic to expect him to be the next Trivino, he could make a similar impact. The righty’s mid-90s fastball and filthy changeup and slurve make him a tough at-bat. We also saw in Houston that the former starter is more than capable of going multiple innings.

With such an unreliable rotation, the A’s will likely need more than two relief arms per game to hold a lead. Wendelken deserves to be in that mix, and should be the next man up if Trivino/Treinen are unavailable. Melvin also can’t be afraid to leave Wendelken on the mound for an extra inning if he is cruising. However, after missing 2017 due to Tommy John Surgery, workload does remain a concern.

Ryan Buchter

As the bullpen’s only lefty, Ryan Buchter fills an essential role, but he has been unreliable at best to start the year. His 6.00 ERA isn’t pretty, and more than once he has been called upon in a pivotal spot and failed to retire a left-handed batter.

Buchter is one of baseball’s few true LOOGYs remaining, and for good reason. In 2018, he limited lefties to a .222 wOBA, but righties crushed him to the tune of a .360 wOBA. In this season’s tiny sample, the split has been even more exaggerated, as Buchter has allowed a .293 wOBA to the 15 lefties he has faced and a .503 (!!!) wOBA to the 18 righties. Five of his six walks have come against righties as well.

The lefty is off to a very strange start to the season. His 27.3% strikeout rate is incredible, while his 18.2% walk rate is atrocious. His fastball velocity is up half a tick and his .374 xwOBA is slightly lower than his .406 wOBA. I expect Buchter to find his control soon, and once he does he’ll continue to be a reliable LOOGY. He’s no Sean Doolittle, and I still wish the A’s had added a second bullpen lefty in the offseason, but he is a very serviceable southpaw.

Fernando Rodney

Easily the most controversial member of Oakland’s bullpen, 42-year-old Fernando Rodney is the oldest player in the league. Full disclosure: I have been a huge fan of Rodney for years now. But personal bias aside, I think there’s reason to believe he’s better than his 2019 results would suggest.

Rodney’s 10.29 ERA, 16.7 K% and 13.9 BB% are all awful. They’re exactly what you might expect from a washed-up veteran that’s played one season too many. But! His .294 xwOBA ranks sixth-best on the team, just ahead of Frankie Montas. This is a result of his low exit velocity allowed and insanely high 64.0% ground ball rate. Based on the batted ball data, Rodney has been incredibly unlucky and, especially given Oakland’s above average infield defense, should have an ERA somewhere in the low threes.

Additionally, I believe Melvin has used Rodney poorly at times. In two of his eight appearances, Rodney entered in the middle of an inning with runners on base. Both times, he allowed at least one inherited runner to score. For his career, Rodney has never been that kind of “stopper.” He’s always needed the first few pitches of an outing to get his velocity and command where they need to be. Those first few pitches can’t come in a tight spot — that’s just asking for disaster.

I’m not saying Rodney is an All-Star, because he obviously isn’t. He’s nowhere near as good as Treinen or Trivino, and he’s at least a full notch below Wendelken and Soria (when the latter is going right). But he still has the velocity and stuff to be successful, and if not for some unlucky batted ball distribution that would already be clear. He should be Melvin’s go-to when the team is trailing by a run or two or up by four or more.

Liam Hendriks

After his poor outing as the Wild Card game opener, Liam Hendriks doesn’t have himself many fans either. But, like Rodney, batted ball data suggests he should be a perfectly capable middle reliever.

Unlike Rodney, Hendriks has the results. After nine appearances, he boasts a shiny 1.69 ERA. But his peripherals — an ugly 5.07 FIP and 5.94 xFIP, along with just a 2.3 K-BB% — present this as a fluke. And I’d agree, Hendriks is unlikely to keep this going all season long. But he might still be a good reliever. He has generated tons of weak contact, as his .276 xwOBA is very good and his .233 xwOBACON (one of the best-named metrics of all time, which measures expected weighted on base on contact) is elite.

Ever since his return from Triple-A last season, Hendriks has thrown hard. He is still averaging 94-95 MPH this season, often with late life. He should be fine in a middle relief role, and I wouldn’t mind seeing him open a game every now and then.

Yusmeiro Petit

Finally, rounding out the bullpen is perhaps its most underrated piece, veteran righty Yusmeiro Petit. He was incredibly valuable for the A’s last season, totaling 93 innings of a 3.00 ERA. But, to me at least, he seems almost forgotten this year.

Petit has thrown nine innings over nine appearances this season, which doesn’t seem too unusual. But he was only trusted with a lead in one of those games, Oakland’s 10-3 win over the Orioles on April 10. Why doesn’t Melvin seem to trust the righty, especially with Soria and Rodney struggling?

His 2.00 K/9 and declining fastball velocity — from 89.3 in 2018 to 88.6 in 2019 — are certainly reasons for concern. But given the small sample and his lengthy track record, I still expect both to rebound at least somewhat for the 34-year-old.

Given the unreliability of the starting rotation, the A’s will need to trust Petit in the middle innings this season. His ability to throw multiple innings was huge last year and will be important again this year. Hopefully we see more of him going forward.

Oakland’s bullpen was phenomenal in 2018 and retained most of its key members. Entering 2019, it was projected to be one of baseball’s best and a 21-game sample should not significantly change that.

As a unit, the A’s pitching staff has actually been incredible at limiting hard contact. Even including the starters, Oakland’s .292 xwOBA ranks third in the league behind only Tampa Bay and Houston, while their .311 xwOBACON ranks first. Despite uninspiring strikeout and walk numbers (which I’d bet will turn themselves around soon), the A’s staff still may be deserving of better results than they’ve had.

The bullpen has, without a doubt, been a disappointment this season. But with better batted ball luck and a little smarter usage of guys like Buchter, Petit and Rodney, it could transform back into the elite unit it was supposed to be.