Boston Red Sox: 5 key spring training roster battles

Spring training is officially here. The Boston Red Sox have had a busy offseason, but there are still questions to be answered.

Several spots on the Red Sox Opening Day roster are undecided as spring training begins

While a few positions seem to be set in stone, there are a few positions battles that will likely be won in spring training. Here are 5 positions and the respective candidates to watch this spring.

Red Sox back-up catcher (Connor Wong or Jorge Alfaro)

The Red Sox brought in catcher Jorge Alfaro this offseason, but not necessarily to be the team's backup catcher. Alfaro was signed on just a minor league deal, while Reese McGuire and Connor Wong are the only two catchers on the 40-man roster. This establishes a three-man race for the major league roster. McGuire should have cemented the starting job after a strong showing in 2022. The backup spot could go to whoever has the better spring.

Connor Wong is yet to figure out big league pitching. In his 33 major league games, he's hit .213/.290/.361 with a .651 OPS, 78 OPS+, and 1 home run. His AAA line is better, as he posted a .838 OPS in 81 games last season, but plenty of players have shown success in AAA while failing to replicate that success in the MLB. At 26, Wong's AAA hitting stats are unimpressive. Defensively, he looks just fine, but with a very small sample size; he has, however, shown excellent arm strength.

Jorge Alfaro has shown flashes in his career, and he rebounded after two poor seasons, hitting .246/.285/.383 with a .667 OPS and 94 OPS+ in 2022. That's about on par with his best seasons, so fans can probably expect him to put up similar or worse numbers in 2023. His glove is worse than Wong's, though he's actually shown even better arm strength, a pop time in the 96th percentile, per Baseball Savant.

Neither are top-tier catchers at this stage, and neither are likely to be the team's starting catcher; however, Alfaro has a better track record in the MLB. He also comes with much more experience than Wong, and while Wong could still have the higher ceiling if he figures out his bat, Alfaro is a safer backup option. I expect him to break camp with the team, but the spot could go to either catcher.

Red Sox 4th Outfielder (Rob Refsnyder or Jarren Duran)

Barring a big surprise from Wilyer Abreu, or another move, this is likely a 2-man battle for the 4th outfielder. The other contingency is Kiké Hernández at CF and Adam Duvall on the bench, but even still, there is a need for another bench bat.

Rob Refsnyder was incredible last year. He hit for a 143 OPS+ while playing at each spot in the outfield. He also has a canon of an arm - 90th percentile arm strength, per Baseball Savant. As of now, it looks like there is no reason Refsnyder shouldn't crack the Opening Day roster. Sure, he doesn't have a great track record, but he played so well last year that he's worth keeping around.

Jarren Duran, however, could make his case. The former top prospect is yet to prove himself in the majors. It looked like 2022 was going to be his year; in his first 15 games, he was hitting .344/.394/.557 with a .951 OPS on July 2nd. He'd then go 24-for-143 with 51 strikeouts and a .515 OPS in his last 43 games. He was also doing this with some notoriously bad defense. Every metric says he should play good defense - according to Baseball Savant, he's 93rd percentile in Sprint Speed, 69th in Arm Strength, and 69th in Outfield Jump. But OAA (-2), DRS (-9), and UZR (-6.4, -17.6/150) all say he's a poor defender.

If the Red Sox choose to keep Jarren Duran - and the fact he's still on the team suggests they want to - he should probably start the season in AAA. Duran, at this point, needs consistent playing time to figure things out. There's a good chance he comes up later in the season, but it's a make-or-break year for Duran, who's on his last option. With another failed stint, Duran's tenure with the Red Sox could be over.

Red Sox 5th starting pitcher (Nick Pivetta, James Paxton, or Tanner Houck)

The Red Sox rotation is a high risk, high reward group. Chris Sale will be in the rotation as long as he's healthy; he's still the team's ace, but he's pitched just 48.1 innings over the last three seasons. Brayan Bello has a high ceiling this season, but he's a 23-year-old entering his first full season, so it's hard to set expectations too high. Garrett Whitlock looks to be staying in the rotation this year, a role he handled pretty well last year. New signee Corey Kluber is also a lock for the rotation, assuming he stays healthy. That leaves one remaining spot, and it'll likely come down to Nick Pivetta, Tanner Houck, or James Paxton.

Nick Pivetta has been a pretty reliable starter the past couple years. While he probably has the lowest ceiling of any of these options, he could probably offer the most innings, tossing 179.2 innings in a league-leading 33 starts in 2022. He did this, however, with a 4.56 ERA and 92 ERA+.

If the Red Sox want to get risky, they could offer the job to James Paxton. Paxton has pitched just 21.2 innings in the past 3 years, but before that, he was an All-Star caliber pitcher with the Mariners and Yankees. He's now 34 and a full year removed from pitching at any level, so realistically, he starts in the bullpen and works his way toward a long relief or spot starter role.

Chaim Bloom spoke with MassLive earlier this month and seemed very hesitant on the idea of James Paxton joining the bullpen; perhaps he's actually the frontrunner for the rotation job.

Tanner Houck might work out better in the bullpen than in the rotation. In 13 starts in 2021, he had a 3.68 ERA with 11.2 K/9, and in 28 relief appearances in 2022, he had a 2.70 ERA with 8.9 K/9. Houck has never pitched more than 70 innings in a season, so his track record is still hard to measure, but he looks better as a reliever than as a starter.

Recently, we discussed how Tanner Houck's versatility is his biggest weapon, and the Red Sox could opt to keep Houck in the bullpen to leave him as a multi-inning reliever who can fill in for injured starters.

Assuming all three are healthy out of spring, James Paxton actually seems to be the favorite to join the rotation. He has a higher ceiling than Pivetta, and Houck's versatility is too valuable to pass up.

Red Sox Final Bullpen Spots (lots of options)

The Red Sox invested heavily into their bullpen this offseason, adding Kenley Jansen, Chris Martin, Joely Rodriguez, and Richard Bleier. They should join John Schreiber and whoever doesn't join the rotation, whether that's Tanner Houck, Nick Pivetta, or James Paxton. While Fangraphs currently projects Kutter Crawford to be the final member of the bullpen, that's assuming Bryan Bello is in AAA. Given the potential for injuries or trades before opening day, who are the candidates to fill out the back of the bullpen?

Crawford was pretty unspectacular as both a starter (5.43 ERA) and as a reliever (5.63) in 2022, though he struck out 22 hitters in 16 innings as a reliever for a 12.4 K/9. He could work across a full season, but the Red Sox will likely give a chance to quite a few different guys throughout spring training. Joining him as an apparent option is Ryan Brasier, who posted an odd split of a 5.78 ERA with a 3.61 FIP in 2022 and seems to be favored by Chaim Bloom.

Wyatt Mills was acquired from the Kansas City Royals earlier in the offseason. He excelled at limiting Home Runs last season, though he's not an overpowering strikeout or velocity pitcher. Neither is Zack Kelly, but he had a 4.28 FIP and 4.33 xFIP thanks to a 2.6 BB/9 in 2022. Kaleb Ort has been an excellent strikeout pitcher in the minors, but that didn't translate to the majors in 2022. He survived a wave of DFA's this offseason, so perhaps the Red Sox are still hoping he can break out.

After that comes a wave of starting pitchers who could break camp as a reliever. Chris Murphy will get a shot in spring training, but he struggled mightily in AAA as a 24-year-old with a 5.50 ERA, 4.9 BB/9, and 6.9 K/9. Josh Winckowski, with his low strikeout rate and high Home Run rate, also doesn't seem to have the makings of a reliever. Brandon Walter should get a look in the majors at some point this season as a spot starter - he posted a 2.88 ERA with 1.1 HR/9, 0.5 BB/9, and 12.2 K/9; he didn't get much of a look in AAA, but he could surprise in spring training and make the bullpen, though it's more likely he'll start out in the AAA rotation. Bryan Mata, with his excellent fastball touching 100 MPH and good offspeed stuff, could be a good choice for the bullpen; he'll have to settle down on his walks, but he posted an 11.4 K/9 across four levels in the minors last season. The longtime prospect could finally get his chance to pitch in the big leagues this season.

Whoever makes the final spot of the bullpen will depend on how they perform in spring training. Chaim Bloom has highly favored Ryan Brasier this offseason (per Chris Cotillo of MassLive), and he could be a lock at this point. Zack Kelly, Kaleb Ort, and Wyatt Mills all survived a wave of DFA's, so they should all be squarely in the mix. But look out for Bryan Mata to have a solid spring and contend for the bullpen.