Arizona Diamondbacks GM Mike Hazen calls bullpen philosophy shift ‘natural change’

Arizona Diamondbacks general manager Mike Hazen acknowledged that the team’s bullpen has struggled for two seasons now.

However, the issues in 2022 were highlighted by the fact the team was better and in a better position to win most nights.

“In 2021, we were in a tough spot by the third inning every night,” Hazen said on a Zoom call with reporters Tuesday. “Last year we were in a great spot until later into the game most nights.

“We’ve always known when we were going to be a good team, that good teams have good bullpens and we were always going to have to be able to build those bullpens.”

The 2022 D-backs bullpen saw improvements from 2021. In fact, its ERA improved by half a run, as did the performance across several ERA estimators — FIP, xFIP and SIERA.

ERA estimators try to isolate the pitcher’s performance based on things they can control, like strikeouts, walks and quality of contact.

Hazen said a lot of what comes from the bullpen hinges on what the rotation provides.

“You have to aggregate enough starting pitching that you can feel good about where you’re going to be to get through a season for your starters,” Hazen said. “In 2021, our starters all got hurt and we won 52 games. Last year, our bullpen wasn’t very good and we won 74 games.

“The downstream effect of having those starters is more damaging than piecing together a bullpen. But we’ve been trying to push resources into our bullpen for the last year, I just didn’t do a good job of it last year.”

The philosophy is less about who the player is and rather what they’re capable of.

For example, the recently-acquired right-hander Carlos Vargas has a fastball that tops out at over 100 mph. Since 2018, the Diamondbacks have four seasons with an average bullpen fastball under 93 mph.

However, the league average fastball from a reliever since 2018 is 93.4 mph.

“We lack power in our bullpen, hard stuff, swing-and-miss stuff,” Hazen said. “We put too many balls in play late in innings relative to other bullpens in the league.

“These are some of the chances and the risks that we’re going to start taking.”