2025 Red Sox Season Preview: Starting Rotation Depth

New York Mets v Boston Red Sox — Photo by Maddie Malhotra/Boston Red Sox/Getty Images

Because in 2025, you need rotation depth

Depth is boring. It’s also incredibly important, especially when it comes to pitching. Pitching injuries are going to happen. Look at the Dodgers. Without pitching depth, injuries to the rotation would have sunk their season. Instead, they were able to win the World Series, thanks to pitching depth (and a loaded lineup).

For the first time in the last few seasons, the Red Sox appear to be equipped with quality rotation depth. With early injuries delaying Brayan Bello and Kutter Crawford’s spring preparation, depth may play a role early in the season. Here’s a quick look at some of the names that may come into play.

Richard Fitts

Craig Breslow won the Alex Verdugo trade. Richard Fitts made four starts in 2024 and wasn’t overly impressive, but those four starts were still better than watching a full season of Alex Verdugo.

Fitts only allowed four earned runs over 20 innings, however, a look under the hood shows that he may have been fortunate. The righty only struck out nine of 85 batters faced. He was able to throw strikes and get into good counts, but his execution with two strikes wasn’t that of a big-league starter. He’ll have to be better at putting hitters away to stick in the rotation going forward.

After his second spring training outing, we can see that Fitts put in some work over the offseason. His fastball averaged 97 MPH, up about 2.5 MPH from last season. While it remains to be seen if that can stick over a full outing, Fitts is ahead of where he was at this time last year. In Fitts’ lone StatCast-enabled spring training start last year, his fastball averaged just 94 MPH. He toyed with a sinker as well last week, which could be an additional weapon against right-handed hitters.

Fitts also did some work on his secondaries over the winter. His slider came in a few miles per hour harder and had a tighter movement pattern. The new version provides more separation from his sweeper, which will hopefully help Fitts miss bats. He also threw a few curveballs on Friday, which could be another weapon to get lefties out.

There’s a lot of spring training to go, but I really like the adjustments Fitts has made so far. As I mentioned, he barely got any swing and misses in his few appearances last season. His newfound velocity, along with the other tweaks, could go a long way in providing more strikeouts. His outing on Friday reminded me a lot of Nick Pivetta in the best way possible. Pivetta with more velocity? Sign me up.

Cooper Criswell

If you’re reading a piece about Red Sox pitching depth, you probably know who Cooper Criswell is. The righty made 18 starts as well as 8 relief appearances last season. For reasons I don’t fully understand, he has an extra option year in his contract, allowing the Red Sox to keep him in Worcester to begin the season if necessary.

Criswell is a side-armer who doesn’t have much projection left at this point. He throws a low 90s sinker that does a good job jamming righties, as well as a huge sweeper that mirrors the sinker. He also has a changeup that gets righties to both whiff and hit the ball on the ground. Against lefties, he employs a similar mix, but he trades in some sinker usage in favor of a cutter.

This can all work, but it isn’t what you want every five days on a competitive team. Of his 18 starts last year, he completed the sixth inning just twice. Criswell doesn’t have the stuff to consistently win in the zone. He has to nibble and rely on command and deception to get hitters out. The more times hitters see his stuff, the easier it is for them to lay off those waste pitches and keep their sights over the plate. Criswell has his role, and he’s great at it. Just don’t expect him to become the ace of the staff.

Quinn Priester

Quinn Priester was acquired at the trade deadline last season as a move for the future. He appeared in eleven games last year (one with Boston) and posted a 4.71 ERA in about 50 innings. He’s totaled 116 major league innings over the last two years. Over those two seasons, he’s been tough on righties while struggling against lefties. This is fairly common as primarily a sinker/slider pitcher, but that doesn’t mean Priester is a finished product.

Against righties, I don’t think Priester has to change much. His sinker lands in the strike zone often but still racked up groundballs thanks to some unexpected drop from his arm slot. He’s also added velocity since leaving Pittsburgh, which should help limit some hard contact. In terms of secondaries, Preister’s slider and curveball have each been solid against righties as well.

As I mentioned, lefties have been a different story. In 2024, he used all five of his pitches about 20% against opposite-handed hitters. We’ll start with his four-seam fastball. He should (and will) stop throwing it entirely. The pitch returned an abysmal 5.2% swinging strike rate and 46.7% hard hit rate. He probably won’t be throwing it anymore, unless it’s a surprise two-strike offering, so I’m not sure why I’m even talking about it.

In place of the four-seam, it appears that Priester will be throwing a cutter. In his first Statcast-enabled spring training start, he used the pitch 11 times, sorting out how it will look in a game setting. The pitch has solid vertical lift, but I’m not sure it has the cut to miss barrels effectively. If he can command the pitch well, locating it up and in against lefties, he might be successful. His slider also showed more lift early in spring training, leading me to believe he wants to use it in the zone, also in place of the four-seamer. If he’s successful, those two pitches along with his curveball could present a path forward versus lefties. Improvements to his changeup would also be beneficial, though he’s never shown the ability to command it consistently, limiting its upside.

Priester’s upside depends on how well he performs against left-handed hitters. Velocity gains made over the offseason should help to a degree, but he’ll need to find a pitch in his arsenal to get strikes and miss barrels, as well as one to put hitters away. His cutter and slider could be the strike-getters, while his curveball and changeup can get whiffs. If he still doesn’t have that pitch, maybe the Red Sox use a left-handed opener on days when Priester is the “bulk pitcher”. Maybe he settles in a bullpen role where Alex Cora can play the matchups. Either way, I’ll be keeping a close eye on Priester as camp rolls on.

Patrick Sandoval

Sandoval is the lone newcomer to this group. He signed a two-year deal with the Red Sox this offseason, though he’ll spend at least part of the first year rehabbing from internal brace surgery. At some point this season, he may figure back into the plans one way or another.

Sandoval has struggled each of the last two seasons but has the potential to be a very good pitcher. His changeup is excellent, which is basically a cheat code for left-handed starters. It’s his best pitch and the one he leans on most against righties. He also uses a slider that he can throw in the zone versus righties. The slider found a bit too much of the zone against lefties last season, but previous success indicates better command can make the pitch effective.

Sandoval uses a four-seam and sinker as well. The four-seam is not good, has never been particularly good, and probably won’t be good in the future. We can go ahead and ditch that, save for maybe two strike counts against righties. The sinker is potentially useful, though. Against lefties, the pitch had a 66% groundball rate in 2024. He didn’t command it well last season, but he’s had a handle on it previously and may have been mechanically off due to injury.

Despite his recent statistics, there’s some stuff to like about Sandoval. Even with poor fastballs, he’s shown the ability to get by with a secondary-first approach. He’s always had swing-and-miss stuff but hasn’t put it together for extended periods. When Sandoval returns from injury, the Red Sox pitching lab may be able to make him a more consistent presence in the rotation.

Overall, this is a very solid group of pitchers who can fill out the back end of the rotation when necessary. Pitching injuries are always going to happen. Kutter Crawford looks like he’ll start the season on the injured list, and Brayan Bello may also be delayed. Unlike past teams, this team feels more equipped to navigate injuries to the rotation without leaning too hard on the bullpen. As of now, Richard Fitts excites me most, but I wouldn’t be surprised to see Cooper Criswell get the fifth spot due to his consistency and experience.

This is the best I’ve felt about the Red Sox pitching depth in several years. Unlike the past two seasons, the team can handle an injury or two or even manage innings for some of their more established starters. Remember, there’s no such thing as too much pitching.