Tony Vitello had no shortage of challenges awaiting him when he leapt from college to the pros, but San Francisco’s front office could’ve made his life easier by substantially investing in a bullpen and establishing a clear hierarchy.
Despite a promising first month of relief pitching, the preseason concerns surrounding the bullpen are proving to be correct.
The Giants’ devastating 8-6 walk-off loss on Friday night to the Colorado Rockies in Denver was the latest sobering reminder of how little the front office devoted to the bullpen during the offseason.
Caleb Kilian inherited a three-run lead going to the bottom of the ninth on Friday but allowed a game-tying three-run homer to Hunter Goodman and a walk-off two-run homer to Ezequiel Tovar.
While Coors Field is notorious for these types of dramatic swings — the first hit Kilian allowed deflected off of first base — there’s no escaping the reality that the Giants lack proven high-leverage relievers.
“The last inning, obviously, is a bitter pill, one that we’ve experienced before,” manager Tony Vitello told reporters in Denver.
Kilian’s blown save was the seventh by a Giant this year, and the seven runs that he and Keaton Winn combined to allow on Friday raised the bullpen’s ERA to 4.04 in May. At the end of April, the bullpen’s 3.19 ERA was the best in the National League.
The bullpen figured to have its challenges, especially with All-Star Randy Rodríguez out for the season after undergoing Tommy John surgery. Still, the Giants’ front office dedicated minimal financial resources to the bullpen, which now ranks 28th in the majors in strikeouts.
San Francisco signed four relievers — Ryan Borucki, Sam Hentges, Jason Foley and Rowan Wick — to major league contracts, but none of the four are helping lock down the later innings.
Wick won’t be available until 2027 after undergoing Tommy John surgery last fall. Foley has closer experience but is still rehabbing from right shoulder surgery. Hentges’ stuff hasn’t rated out the same after undergoing left shoulder surgery in 2024 and right knee surgery in 2025. Borucki has a 4.15 ERA over 21 2/3 innings and is seldom used in leverage situations.
Ryan Walker was the closest the team had to a closer entering the season, but the Giants optioned him to Triple-A Sacramento this month after posting a 6.46 ERA over 15 1/3 innings. Walker was optioned on May 10 but didn’t make his first appearance with Sacramento until May 20, suggesting he potentially spent some time working through his mechanics.
“I know he put in his work in the offseason, but your mind has a lot to do with everything,” Vitello said at the time Walker was optioned. “I think the biggest thing is making sure, whether it’s him or our team, you’re feeding your narrative that you want to choose to feed yourself every day, which is really challenging, especially at this level. So, mentality I think, is the key.”
In fairness, the Giants’ current high-leverage options don’t lack in the stuff department. Kilian, Winn and Erik Miller all boast above-average stuff, according to FanGraphs’ Stuff+ model. Miller, in particular, is one of the nastier lefty relievers in the game when he’s right. But as time has proven, getting those final three outs in a game is a different beast compared to the first 24.
As far as maximizing the current group, one option for Vitello could be to give more closing opportunities to Miller, who recorded the first three saves of his major league career before hitting the injured list. Another gambit at his disposal: naming a closer and settling the bullpen in defined roles. The return of Foley, who has made six rehab appearances, should hypothetically help as well.
Regarding the personnel, one reliever in Sacramento with major league high-leverage experience is veteran right-hander Michael Fulmer. The 33-year-old has recorded 19 saves in the majors and is currently 5-for-7 in save opportunities with the River Cats. Despite a high walk rate, Fulmer is currently striking out 28 percent of the batters he’s facing in Triple-A.
Along with Fulmer, right-handers Gregory Santos and Dylan Smith could be worth second looks after briefly spending time in the majors this season. Walker will likely return to the majors at some point this season as well, the only question being when. The Giants may also want to evaluate whether it’s necessary to have four lefty relievers, an abnormally high amount for any bullpen.