Potential D-backs Free Agency Target: Andrew Kittredge

The veteran setup man had excellent results in 2024, and could be a low-cost bullpen option.

Aug 9, 2024; Kansas City, Missouri, USA; St. Louis Cardinals relief pitcher Andrew Kittredge (27) pitches during the eighth inning against the Kansas City Royals at Kauffman Stadium. Mandatory Credit: Jay Biggerstaff-Imagn Images / Jay Biggerstaff-Imagn Images

This article is part of a series evaluating potential free agent and trade acquisitions for the Arizona Diamondbacks entering the 2025 season.

The Diamondbacks' bullpen was one of the club's greatest strengths in 2023 down the stretch, but it certainly lacked depth, and a bottom-five bullpen ERA in 2024 was a major contributing factor to Arizona being left out of the playoffs.

Relievers are, of course, volatile acquisitions. Some of general manager Mike Hazen's biggest successes have come from the bullpen, as have some of the D-backs' less beneficial moves. But a club will almost always look to strengthen their relief corp, even with some of the best results.

2025 is no different, and there's plenty of options to choose from. It might be difficult to land some of the more highly-touted options, so a potential low-cost addition with consistently good results is worth examining.

RHP Andrew Kittredge - St. Louis Cardinals

Right-handed veteran reliever Andrew Kittredge had a successful season with the St. Louis Cardinals in 2024.

After suffering an elbow injury in 2022, he underwent Tommy John Surgery, and didn't pitch again until August of 2023. Despite the missed time, he immediately pitched to a 3.09 ERA and 3.43 FIP, though only pitching 11.2 innings.

In 2024, he bounced back, pitching to a 2.80 ERA over a near-career-high 70.1 innings, serving as the Cardinals' primary setup man. Ahead of 2025, he's a free agent, with FanGraphs' crowdsource estimate expecting a mere one-year, $3 million deal for the righty.

But is he a good fit for the D-backs?

Pros

Results

Ultimately, Kittredge has been consistently good in his overall results. Especially coming back from an injury as severe as his, it's encouraging to see him settle immediately back into an ERA as good as 2.80.

Although he hasn't pitched as much due to his injury of late, he's delivered an ERA below 4.00 for the last five straight seasons. Since 2020, he's pitched to a 2.47 total ERA, limited walks (2.03 BB/9), and induced ground balls at an above-average 48.8% clip.

Longevity

When Kittredge has been healthy, he's been at his best. Sure, the injury is absolutely a concern, but his fastball velocity hasn't taken much of a hit, and he still stays well above 94 MPH on his sinker - his primary fastball.

Though he's pitched short seasons in 2020, 2022 and 2023, the years he's pitched career-high innings have been his best from a raw production standpoint.

In 2019, he pitched 49.2 innings in his third year of MLB action. While his ERA was a pedestrian 4.17, his FIP (3.56) and xFIP (3.25) suggested he was a better pitcher than the ERA showed, and his K/9 was an impressive 10.51.

In 2021, he pitched 71.2 innings, resulting in a 9-3 record and brilliant 1.88 ERA, while striking out batters at a 9.67 K/9 rate.

In 2024, he pitched 70.2 innings coming off Tommy John Surgery, and pitched to an excellent 2.80 ERA.

Arsenal/Chase Ability

In 2024, Kittredge forced opposing hitters to chase outside the zone at a 38.9% rate, 100th percentile in MLB. That's not an outlier either, he's induced chases at a high rate for most of his career, and ranked at or close to the 100th percentile in numerous seasons, even the injury-shortened ones.

Most of those chases come from his devastating slider. The righty has a unique delivery and variable arm angle, and his slider ranks high in velocity (88.1 MPH) and movement (4.1 total inches vs comparable).

He also throws a 94-95 MPH sinker, an occasional 94 MPH four-seam fastball, and a very infrequent cutter. For the most part, he's a two-pitch arm, but his slider remains a top-tier weapon when its movement is up to par.

Cons

Peripherals

In baseball, all that ultimately matters is results. If your ERA is good, your team is more likely to win when you enter the game. With that said, Kittredge's peripheral numbers are a bit of a concern, and suggest he might not be as proficient a pitcher as his ERA numbers suggest.

In 2024, his FIP (3.96) and xERA (4.05) were starkly different from the 2.80 ERA that his success was measured by. On top of that, his BABIP was a mere .263, a number that likely won't be sustainable.

That's been a trend throughout his career. In 2021, his best career season, his ERA might have been 1.88, but his xERA, FIP and xFIP all hovered around the low-3.00s. Those numbers aren't necessarily poor by any means, and indicate he was quite good that year, but still show he's been on the right side of batted ball luck and good defense.

Since 2019, he has a 2.84 ERA, but a 3.59 FIP. He's certainly been solid, but not quite as good as the raw results might suggest. His sinker has been hit quite hard of late, and lost some of the movement that made it effective, though the velocity hasn't taken much of a hit.

Splits

Perhaps the most concerning aspect of Kittredge's numbers are his platoon splits. Right-handers have struggled, particularly against his slider. But lefty bats have crushed him. In 2024, he allowed a .188 average and .297 slug to righties, but those ballooned to .296 and .571 respectively against lefties.

For his career, lefties have slugged him at a .455 clip, while righties have only managed a .378 slug against.

His career splits are inflated by the exceptional disparity of 2024, but in an era of MLB where it's impossible to protect your pitchers from bad matchups, that could be a serious issue if the trend continues to worsen.

Conclusion

Ultimately, paying just $3 million for a solid (if not elite) reliever is a potential value signing. If the D-backs were to keep Kittredge out of the setup role, and utilize him more as middle relief or high-leverage depth, he could be worth a cheap one-year contract.

But he is 34, and there's a chance his results will start to catch up to his peripherals. It's also possible that his splits were a bit fluky. But even if he pitches somewhere in the mid-3.00s, that's a worthy investment.

If the price tag truly is only $3 million, that's good potential value for a guy who's delivered fairly consistent results, even if he's not quite a high-leverage caliber arm. Ultimately, it depends on how the ball falls, but Kittredge would likely be a low-risk, low-reward signing for the D-backs.