When did the D-backs’ bullpen become one of MLB’s best?

PHOENIX — Arizona Diamondbacks manager Torey Lovullo gave the bullpen a lot of credit for his club’s position on the doorstep of clinching a postseason berth.

The D-backs have a 2.20 ERA in September in 106.1 innings out of the bullpen, which ranks third behind division winners in the Milwaukees Brewers and Los Angeles Dodgers.

Not only has the back end stabilized with closer Paul Sewald and setup man Kevin Ginkel, but nearly the entire group is on a heater.

Ryan Thompson, Luis Frias, rookie Andrew Saalfrank, Joe Mantiply and Miguel Castro have combined for 53.2 innings and three (!) earned runs in September.

“Everybody’s been picking each other up and it seems everybody wants the ball, so that’s a good thing,” Mantiply said. “Everybody’s feeling good. I mean, we’re all just ready to go out and do what we got to do.”

The success out of the bullpen has allowed the Diamondbacks to shift its pitching staff in the home stretch.

Arizona cut down its starting rotation by releasing Zach Davies (-1.5 rWAR) this week. Rookies Ryne Nelson and Brandon Pfaadt can provide length as starters, but Lovullo is relying on his arms out of the pen for extended innings to build out games.

“As of right now, it’s Zac (Gallen), Merrill (Kelly), TBA and I think the reasons are obvious. We’re just trying to figure things out,” Lovullo said.

There is no announced starter for Sunday’s season finale, which could have playoff implications depending on the outcome of Saturday’s game against the Houston Astros. Arizona needs one win to clinch, but even so, Gallen and Kelly would not be available on normal rest for Game 1 of the NL Wild Card Series.

“I’ve had that conversation with myself about what that would look like,” Lovullo said. “If we punch our ticket, we will start to have those conversations.”

Arizona having a bullpen to lean on has been far from the case for many stretches this season. The D-backs had the highest reliever ERA in baseball from the start of July through Aug. 16 at 6.18 with eight blown saves.

Lovullo made a comment two weeks ago after pulling Pfaadt at 73 pitches that he may not have felt comfortable doing so with the state of the bullpen two months ago.

So what is the difference? When did the switch flip?

D-backs’ bullpen differences

Changing the personnel

This group has gone through a lot of change after the Diamondbacks signed Andrew Chafin, Scott McGough and Castro last offseason to reinvigorate a bullpen.

The three found success in middle to low leverage situations but struggled to lock down games in the ninth inning (24 saves, 11 blown saves), minus McGough’s near scoreless June.

Chafin was dealt away at the trade deadline, Castro was moved to a middle relief role and McGough is now on the injured list (shoulder).

The Diamondbacks, after months of fluidity, sought a closer at the deadline and traded for Sewald from the Seattle Mariners. Ginkel fit into the setup role and allowed Lovullo and his staff to match up the rest of the group.

“It’s been definitely a revolving door, for sure,” reliever Kyle Nelson — who has been in the bullpen since Opening Day — said. “Each stage of the season, the differences in the groups we’ve had have had their share of good and bad. The unit we have down there right now is obviously clicking at the right time and has been a big part of this stretch.”

Ginkel ascends

Ginkel has thrived in the second half of the year with a 2.73 ERA, 39 strikeouts and a .526 opposing OPS since his first save opportunity on July 18. Opponents are whiffing at his slider at a 40.4% clip, which he sets up with a fastball he’s throwing less often but with better results.

He was optioned in June despite having a sub-3.00 ERA in a roster shuffle that brought Mantiply and catcher Carson Kelly back from the IL. Ginkel found his way back two weeks later and dominated for the next month to earn save opportunities ahead of the deadline.

“The persistence, the belief in himself and then going out there and executing at a high level with really good stuff, finish to his pitches,” Lovullo said. “He has just a certain attitude that you want every backend guy to have.”

General manager Mike Hazen on Arizona Sports’ Wolf & Luke harkened back to Archie Bradley’s value as an eighth-inning guy in 2017 when illustrating how important Ginkel has been.

The little things added up in a HUGE bounce-back win for these #Dbacks! pic.twitter.com/mXTBscZ8En

— Arizona Diamondbacks (@Dbacks) July 19, 2023

Reinforcements step up

Sewald has delivered in 13 of his last 14 save opportunities, doing exactly what Arizona added him to do even with some traffic on the bases (1.47 WHIP in Arizona).

He is set up to close games in 2024, as well, with another year under team control.

80 in the W column. 👏 pic.twitter.com/ZIXRYmhrwb

— Arizona Diamondbacks (@Dbacks) September 20, 2023

The D-backs seemingly found a diamond in the free agent market with Thompson, who signed a minor league deal with Arizona after getting released by the Tampa Bay Rays.

The D-backs added a few veteran pitchers to minor league deals this year – Nabil Crismatt and Aaron Sanchez, for example – and they found someone to stick. Thompson had a productive 2020-22 in Tampa Bay with a 3.50 ERA in 103 innings before a tough May led to his jettison from the Rays.

“I haven’t had the best year this year, these guys, they’ve shown that they believe in me. It’s nice to be wanted, and I’m just so happy to be here,” Thompson said when he joined the D-backs.

Thompson didn’t allow a run in his first nine innings in Arizona, recording a save in his debut.

Saalfrank still has not allowed an earned run in 10.1 MLB innings after making his debut at 26 years old. He’s pitching in high pressure situations, too.

On Friday, Arizona brought him in to face two of the best left-handed bats in baseball, Houston’s Yordan Alvarez and Kyle Tucker in a two-run game. The rookie recorded both outs without issue.

“You think about who’s carrying the heavy workload, it was Castro, it was Nelson, Ginkel and we’ve got three new arms down there,” Lovullo said. “So I think it’s a really, really strong group with Saalfrank, Sewald and Thompson being those late additions. They’re a very trusted group and because of that we feel very comfortable knowing with three and a half, four starters that we’re going to win some baseball games.”

When did the switch flip?

It wasn’t right at the deadline. The D-backs went on a nine-game losing streak at the time, so Sewald did not pitch for nearly the first week of his tenure. He blew his first save opportunity in Minnesota against the Twins in what felt like a low point in the D-backs’ season.

The second half of August is when the turnaround took shape for both the bullpen and team as a whole. Thompson was added on Aug. 27, Frias recalled on Sept. 1 and Saalfrank called up on Sept. 4.

The D-backs went 28-15 from Aug. 17 until Thursday.

Sunday could be a bullpen day. Tuesday’s Game 1 of the postseason, potentially the first D-backs playoff game since 2017, could be a bullpen day. Pfaadt or Nelson could be used as an opener.

But the D-backs’ personnel requires unorthodox thinking, and that would carry into October.

“It’s a frustrating thought for the baseball traditionalists, and I may fall into that category. But I’ve got to throw all that out the window and do the best thing I possibly can to help this team win baseball games,” Lovullo said regarding bullpen games.

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