Red Sox Bullpen Preview: Will Last Year's Weakness Become a Strength?

Assessing the Red Sox' new-look bullpen for 2023 originally appeared on NBC Sports Boston

Improving the bullpen was a top priority for Chaim Bloom and the Boston Red Sox during the offseason.

That came as no surprise following a dismal year in which Red Sox relievers amassed the fifth-worst ERA (4.59) and ninth-highest WHIP (1.36) in MLB. Boston lacked a go-to closer and its only lights-out arm out of the 'pen, John Schreiber, was overworked and out of gas toward the end of the campaign.

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To remedy those issues, the Red Sox signed Kenley Jansen, Chris Martin, Joely Rodriguez, Wyatt Mills, and a handful of depth pieces. They also traded 2018 World Series champion Matt Barnes to the Miami Marlins for southpaw Richard Bleier.

The overhaul shows a serious effort to turn a glaring weakness into a strength. There is obvious upside with this new-look group. But like the rest of the 2023 Red Sox roster, it includes some risks.

Here's a closer look at the Boston bullpen ahead of Opening Day, including best and worst-case scenarios for each pitcher.

Wyatt Mills, RHP

2022 stats: 4.60 ERA, 1.33 WHIP, 13 BB, 26 SO, 29.1 IP (27 appearances with Seattle Mariners)

The Red Sox acquired Mills from the Royals in December and hope he'll be this year's breakout bullpen arm. The 28-year-old sidearmer's delivery is similar to last year's breakout reliever, John Schreiber. He boasts impressive stuff and that has shown this spring through his 10 strikeouts in six innings pitched (five appearances). If Mills lives up to the hype, he could be the X-factor in Boston's 'pen. If he struggles out of the gate, he could quickly lose his spot.

Best-case scenario for 2023: Mills breaks out as this year's version of John Schreiber.

Worst-case scenario for 2023: Mills loses his spot in the big-league bullpen and fails to make an impact with the club in 2023.

Ryan Brasier, RHP

2022 stats: 5.78 ERA, 1.30 WHIP, 13 BB, 64 SO, 62.1 IP (68 appearances)

Brasier was considered a likely cut candidate after a lousy 2022, but Bloom believes the right-hander is posed for a bounce-back season. He made that clear after he designated Barnes for assignment instead of Brasier in January. Brasier was outstanding during Boston's 2018 World Series run but hasn't been all that effective since. He'll get his shot at redemption, but he should have a short leash in 2023.

Best-case scenario for 2023: Brasier bounces back from his disastrous 2022 season with 2018-like production.

Worst-case scenario for 2023: Brasier's woes continue and the Red Sox finally decide to part ways.

Richard Bleier, LHP

2022 stats: 3.55 ERA, 1.44 WHIP, 10 BB, 32 SO, 50.2 IP (55 appearances with Miami Marlins)

The Red Sox needed to add a southpaw to their bullpen, so they said goodbye to Barnes and acquired Bleier from Miami. Bleier, 35. doesn't strike out many hitters but won't walk many either. The journeyman reliever has plenty of experience pitching in the AL East having previously spent time with the Baltimore Orioles and New York Yankees.

Best-case scenario for 2023: Bleier proves to be an upgrade from Barnes with numbers similar to his 2021 campaign in Miami (2.95 ERA, 0.98 WHIP).

Worst-case scenario for 2023: Bleier shows his age and reverts back to the pitcher he was the last time he played in the AL East, when he posted a 5.37 ERA with the Orioles.

Joely Rodriguez, LHP

2022 stats: 4.47 ERA, 1.35 WHIP, 26 BB, 57 SO, 50.1 IP (55 appearances with New York Mets)

Rodriguez joins Bleier as the only two left-handers currently in the Red Sox' projected Opening Day bullpen. The hard-throwing 31-year-old has "elite stuff" if you ask manager Alex Cora, though he has yet to put it all together over the course of a full MLB season. The strikeout totals are impressive, but he needs to improve his command in order to be a valuable piece for Boston.

Best-case scenario for 2023: Rodriguez shows why Alex Cora said he had "elite stuff" and is the reliable lefty the Red Sox need out of the 'pen.

Worst-case scenario for 2023: Rodriguez is the weak link in the bullpen and struggles to find a consistent role.

Tanner Houck, RHP

2022 stats: 3.15 ERA, 1.18 WHIP, 22 BB, 56 SO, 60 IP (32 appearances)

Houck was one of the Red Sox' more dependable pitchers in 2022 but his season ended on a sour note. The 26-year-old underwent back surgery in August.  If he's back to 100 percent, he'll bring his usual versatility to Boston's pitching staff and could come in handy as a starter. But with his injury history and only three pitches in his repertoire, Houck might be best suited as a reliever for the foreseeable future.

Best-case scenario for 2023: Houck stays healthy and picks up where he left off in 2022 as a lights-out reliever who can also be depended on as a spot starter.

Worst-case scenario for 2023: The injury bug bites Houck again.

John Schreiber, RHP

2022 stats: 2.22 ERA, 0.985 WHIP, 19 BB, 74 SO, 65 IP (64 appearances)

Schreiber was one of the few bright spots for Boston last season. In fact, it wouldn't be a stretch to call him one of the most valuable players of the 2022 campaign. He anchored the bullpen until he finally ran out of gas in the fall. If he can avoid regression, he'll help make the Red Sox' improved 'pen a legitimate strength.

Best-case scenario for 2023: Schreiber proves his 2022 breakout wasn't a fluke and again steps up as one of the Red Sox' most reliable relievers.

Worst-case scenario for 2023: Schreiber's spring training struggles carry into the regular season and the 29-year-old regresses to the mean.

Chris Martin, RHP

2022 stats: 3.05 ERA, 0.98 WHIP, 5 BB, 74 SO, 56 IP (60 appearances with Chicago Cubs and Los Angeles Dodgers)

Martin was a different pitcher after joining the Dodgers ahead of the 2022 trade deadline. The 36-year-old posted a 1.46 ERA and 0.53 WHIP in 26 outings with L.A. Expecting those numbers in Boston is unrealistic, but Martin should be a breath of fresh air with his elite command and high strikeout rate (11.9 K/9 in 2022). He should bring a significant boost as the Red Sox' new set-up man.

Best-case scenario for 2023: Martin duplicates his 2022 production with L.A. and serves as a perfect bridge to Jansen.

Worst-case scenario for 2023: Martin regresses and looks more like his 2021 self (3.95 ERA, 1.27 WHIP with Braves) or early-2022 self (4.31 ERA, 1.34 WHIP with Cubs).

Kenley Jansen, RHP

2022 stats: 41 saves, 3.38 ERA, 1.05 WHIP, 22 BB, 85 SO, 64 IP (65 appearances with Atlanta Braves)

Jansen's résumé speaks for itself. The 35-year-old veteran is a three-time All-Star with a World Series title and a top-five Cy Young finish under his belt. He might not be the elite closer he once was with the Dodgers, but he's still one of the best in the sport. He led the league with 41 saves last season and while he may not get as many save opportunities this year, the Red Sox will be relieved to finally have a proven closer at the back of their bullpen.

Best-case scenario for 2023: Jansen remains among the game's elite closers and gives Boston the stabilizing presence it has lacked at the back of its bullpen.

Worst-case scenario for 2023: Age starts to catch up to the 35-year-old veteran and the closer spot becomes a giant question mark all over again.