Previewing the 2023-24 free-agent class: Lefty relievers

We’ve been covering the upcoming free agent class at MLBTR. After covering the starters yesterday, we’re on to the relief group. We’ll begin with the southpaws.

Note: only players who have been on an MLB roster in 2023 are included. The ages listed are for the 2024 season.

Top of the Class

• Josh Hader (30)

Long one of the game’s most dominant relievers, Hader now finds himself on the precipice of free agency, where he’ll be among the most sought-after talents on the market this winter. He’s no longer the premier strikeout arm in baseball but still sports the fifth-best strikeout rate of any qualified reliever in 2023 at 36.7%. The dip from his days of fanning around 45% of his opponents hasn’t made him any less effective, however. Hader boasts a sensational 1.21 ERA and has allowed all of three earned runs since Memorial Day.

There was some hand-wringing about the lefty’s struggles in the run-up to the 2022 trade deadline and about his early performance following a trade to the Padres. Hader quieted those concerns with a dominant showing both in September and in the postseason. Since being blown up for six runs on Aug. 28, 2022, Hader’s numbers look like this (postseason included): 68 2/3 innings, 1.05 ERA, 37.3% strikeout rate, 11.2% walk rate, two home runs allowed (0.26 HR/9).

Hader has been a veritable bullpen cheat code this season and for much of his career. He’s a lock to receive and reject a qualifying offer, and he’ll reach free agency with his sights set on topping Edwin Diaz’s $102M guarantee — the largest ever for any reliever — and should have a legitimate chance to do so.

High-Leverage Relievers

• Aroldis Chapman (36)

It’s been a resurgent year for Chapman both in terms of velocity and overall results. His heater’s 99.1 mph average is at its highest point since the 2017 season, and Chapman has unsurprisingly seen a notable improvement in his strikeout rate (42.9%) and swinging-strike rate (17.6%). Among 439 relievers who’ve pitched at least 10 innings this year, Chapman trails only Baltimore’s Felix Bautista in terms of strikeout rate.

Overall, the former Reds, Yankees and Cubs closer has pitched to a 2.75 ERA in 55 2/3 innings of work. Chapman’s command is always going to be shaky, and this year has been no exception; he’s allowed a free pass to 14.2% of his opponents. His sky-high strikeout rate has offset that, however, as he’s found success working primarily in a setup role between Kansas City and Texas. Chapman signed a one-year, make-good deal with the Royals this past offseason that guaranteed him $3.75M. He’ll be in line for a considerably heavier payday this time around — quite possibly on a multi-year deal. He should have closing opportunities available to him.

• Matt Moore (35)

It’s been quite the career arc for Moore. A top prospect and burgeoning star with the Rays early in his career, he underwent Tommy John surgery in 2014, returned looking more like a fourth starter and, after being traded two different times, eventually settled into journeyman status. Moore had to settle for a minor league deal with the Rangers in 2022, but he’s found new life as a bona fide late-inning reliever over the past two seasons.

Moore’s 2022 breakout in Texas (1.95 ERA in 74 innings) led to a one-year, $7.55M deal with the Angels in 2023, and he’s continued to demonstrate his efficacy in leverage situations. In 48 2/3 frames between the Angels and Guardians, the southpaw has a 2.77 ERA, 28.5% strikeout rate and 7% walk rate. He’s picked up 21 holds as well.

Claimed off waivers by the Marlins this week, he’ll spend the final week-plus of the season in Miami and hope to help push them to a postseason spot, even though he won’t be eligible for the playoff roster. Dating back to 2022, Moore has a 2.27 ERA and 35 holds in 122 2/3 innings with a well above-average strikeout rate. He’s shown that his 2022 season wasn’t a fluke, and there ought to be multi-year offers waiting for him in free agency.

• Wandy Peralta (32)

Acquired in an April 2021 trade that sent 2019 cult hero Mike Tauchman to the Giants, Peralta wound up providing the Yankees with two and a half seasons of quality bullpen innings. In 153 innings with the Yankees dating back to that ’21 trade, Peralta has turned in a sharp 2.83 ERA with a 21% strikeout rate and 10.3% walk rate. He’s overwhelmed left-handed opponents, held his own against righties, and kept the ball on the ground at a roughly 55% clip — all while sporting a heater that averages better than 95 mph.

Peralta isn’t a household name, but he’s been a quietly solid big-league reliever dating back to his 2020 season with the Giants — evidenced by a 3.01 ERA over 188 2/3 innings in that time. He could find a two-year deal in free agency this winter.

• Will Smith (34)

After an up-and-down tenure in Atlanta over the course of his prior three-year deal, Smith lingered on the free agent market into March this past offseason. He’d turned things around following a trade to the Astros but still seemed to be met with skepticism, as he commanded a modest one-year, $2M deal in free agency.

Through late August, the deal looked to be a bargain. Smith pitched to a 2.96 ERA with excellent strikeout and walk rates, but he’s hit a rocky stretch in the 2023 campaign’s final two months. Over his past 18 1/3 innings, Smith has been charged with 17 earned runs on 22 hits (three homers) and eight walks with 15 strikeouts. It’s ballooned his ERA from 2.96 all the way to 4.55. The veteran lefty’s 24.2% strikeout rate, 7.3% walk rate, 13% swinging-strike rate and 35.4% chase rate are all strong marks, but this recent rough patch could result in him settling for another one-year deal in his return to the market this winter.

Middle Relievers

• Scott Alexander (34)

A ground-ball machine with good command who doesn’t miss many bats, Alexander has tossed 48 1/3 innings of 4.66 ERA ball for the Giants this year. San Francisco has used him as an opener on eight occasions as well. From 2016-22, Alexander notched 216 1/3 innings with a 2.95 ERA and a mammoth 70.1% ground-ball rate. This year’s results aren’t great, but he should get a big-league deal this winter.

• Jake Diekman (37)

Stop me if you’ve heard this one before: the veteran Diekman struggled through rough showings with the White Sox in both 2022 and early 2023 before bouncing back upon signing with the Rays. In 42 1/3 innings, the Diekman has pitched to a 2.34 ERA with a 28.6% strikeout rate and 13.7% walk rate. Command has been a problem for Diekman throughout his career, but he still throws hard and still misses bats at a high level. Tampa Bay hasn’t used him in high-leverage spots, but he’s had success more often than not there and should be in line for another big league deal this winter.

• Brent Suter (34)

A waiver claim out of the Brewers organization early in the 2022-23 offseason, Suter hasn’t been fazed by pitching at altitude. In 64 2/3 innings with the Rox, he’s pitched to a 3.48 ERA — a near mirror image of the career 3.51 mark he carried into the 2023 campaign. Suter’s 18% strikeout rate is the second-lowest of his career, and his 8.8% walk rate is a career-high. However, the soft-tossing lefty has long been one of the game’s best at avoiding hard contact, and that’s true again in 2023: 83.6 mph average exit velocity, 3% barrel rate, 25.9% hard-hit rate. Opponents just don’t square the ball up against Suter, and he’s made a fine career out of that knack for weak contact.

Club Options

• Andrew Chafin (34)

Chafin posted big strikeout numbers with the D-backs but has struggled since being traded to the Brewers, for whom he has a 7.82 ERA in 12 2/3 innings. The veteran southpaw was sporting a 3.06 ERA and matching FIP at the All-Star break — a number that falls right in line with the collective 3.05 ERA he posted in 289 innings from 2017-22. The recent rough patch stems from a small-sample spike in homers (three) and walks (eight) in his short time with Milwaukee. The poor results seem like they’ll lead to the Brewers opting for a $725K buyout rather than Chafin’s $7.25M option price, but he should get a big league deal again in free agency this winter.

• Jarlin Garcia (31)

Garcia didn’t wind up pitching at all with the Pirates after signing a one-year deal, as a biceps injury incurred in spring training ended up shelving him for the season. The Bucs will surely buy out his $3.25M option.

• Brad Hand (34)

Hand’s $7M club option actually converted to a mutual option when he was traded from the Rockies to the Braves, but that’s a moot point. The former All-Star has limped to a 6.00 ERA with Atlanta, and the team will likely pay a $500K buyout.

• Aaron Loup (36)

Loup pitched decently in 2022 — the first season of a two-year, $17M free-agent contract. He’s been roughed up to the tune of a 6.10 ERA in 2023, however. A bloated .373 average on balls in play has surely played a role in that, but his strikeout, walk and grounder rates have all also continued to trend in the wrong direction since his career year with the Mets in 2021 (0.95 ERA in 56 2/3  innings). The Halos figure to pay the $2M buyout on his $7.5M option.

• Brooks Raley (36)

Raley parlayed a successful three-year KBO run into a big league return in 2020, and he’s since solidified himself as a quality reliever. He’s sporting a 2.94 ERA and 25.9% strikeout rate this season, albeit against a questionable 10.3% walk rate. Given Raley’s 2.81 ERA, nine saves and 46 holds in his past 105 2/3 innings, his $6.5M club option seems like a good value. That’s especially true given that it comes with a $1.25M buyout, making it a net $5.25M call. Even if the Mets don’t want to pay that price plus the associated luxury tax fees, he should have trade value.

• Joely Rodriguez (32)

Injuries have limited Rodriguez to only 11 innings this year, during which time he has a 6.55 ERA. The Red Sox shut him down from throwing due to a hip injury back in August. They’re a virtual lock to pay the $500K buyout rather than pick up Rodriguez’s $4.25M option.

• Justin Wilson (36)

Wilson signed a big league deal last winter while rehabbing from Tommy John surgery. The Brewers were likely intrigued by the new slider he’d unveiled with the Reds in a tiny sample of 3 2/3 innings during the 2022 season. Wilson whiffed seven of his 13 opponents with a mammoth 18.5% swinging-strike rate before hitting the injured list and requiring surgery. Wilson completed a 14-month rehab only to suffer a lat strain while warming up in the bullpen for his return to a big league mound. That injury ended his season, and it’s likely the Brewers will decline his $2.5M option in favor of a $150K buyout.

Veteran Depth and Bounceback Hopefuls

• Fernando Abad (37), Richard Bleier (37), Amir Garrett (32), T.J. McFarland (35), Daniel Norris (31), Drew Pomeranz (34), Chasen Shreve (33)

All of these 30-something hurlers have had big-league experience in the past. Abad was a quality middle reliever from 2013-17 but has just 37 big league innings since (6 1/3 coming with the Rockies this year). The soft-tossing Bleier was rocked in Boston this year but had a 3.09 ERA with the O’s and Marlins from 2020-22. Garrett has a history of missing bats for the Reds, but his longstanding command issues worsened with the Royals over the past two seasons. McFarland is a ground-ball specialist with good command but one of the game’s lowest strikeout rates. Norris has missed bats in the past but has also been quite homer-prone. Pomeranz was one of the game’s best lefty relievers but hasn’t pitched since 2021 due to injury. Shreve’s career 3.97 ERA is solid, but he’s been inconsistent on a year-to-year basis recently.

This group figures to draw plenty of interest in minor league free agency over the winter but might have a hard time finding a guaranteed deal due to recent struggles and/or health woes.

Previous installments: catcher, first base, second base, third base, shortstop, corner outfield, center field, designated hitter, starting pitcher.

All stats through play Thursday.