What will Red Sox do at 1B in wake of Casas injury?

BOSTON -- The one thing the Red Sox know about their situation at first base is that Triston Casas won’t play for the rest of the season.

Casas ruptured his left patellar tendon on Friday and will soon have surgery that will require an extensive rehab.

So where does that leave the Red Sox, who lost 4-3 to the Twins on Saturday, at a position they don’t have a lot of depth at?

Here is a look at where things stand.

Short-term solution

Romy Gonzalez, the only other first baseman on the roster as of Friday, will get the bulk of starts in the upcoming days.

The right-handed hitter had a career-high 216 plate appearances last season, slashing .266/.306/.417 with six homers and 29 RBIs. It remains to be seen how he will respond to a higher-volume role. The Red Sox like his athleticism and ability to hit lefties.

Abraham Toro was selected from Triple-A Worcester to take the roster spot vacated by Casas for Saturday’s game. The 28-year-old is a switch hitter who had a career-high 364 plate appearances for the Athletics last season, producing a line of .240/.293/.350 with six homers and 26 RBIs.

However, that doesn’t seem like much more than a bridge until the Red Sox can find a more permanent solution.

Also, chief baseball officer Craig Breslow will examine external solutions. Dom Smith turned into a decent fit last season when Casas missed four months with torn cartilage in his left rib cage. Smith is currently playing at Triple-A for the Yankees.

“Yeah, if [external options] are available,” said Breslow. “We obviously started this last offseason trying to be aggressive in putting a competitive team on the field. And this is unfortunately an opportunity to explore what is available. We'll look both internally and potentially externally as well.”

Can Raffy move to first?

It was well-documented that star slugger Rafael Devers was upset when the Red Sox decided to move the career third baseman to DH following the acquisition of Alex Bregman in February. After a historically rough start to the season in terms of strikeouts, Devers has looked more like himself in recent days, appearing as if he’s found a DH routine that works with him.

“Right now, [we’re] not in a place to speak about that,” said Breslow. “But obviously we'll have conversations internally, and we'll do the best we can to find the short-term solution, and also one that we feel like can hold up over the long term.”

At least at this point, manager Alex Cora doesn’t seem inclined to ask Devers to make another switch.

“From my end right now, no. We asked him to do something in Spring Training. In the beginning, he didn't agree with it, and now he's very comfortable doing what he's doing,” said Cora. “So like I told you guys in Spring Training, he’s my DH.”

But what is to stop Devers from volunteering to make the switch? While a transition across the diamond isn’t easy for everyone, Kevin Youkilis is a player who did it with excellence, winning a Gold Glove Award at first. Youkilis later went back to third and picked up right where he left off.

Moving Devers off DH would solve another problem in that it could open up a roster spot for Masataka Yoshida, who has been on the injured list all season due to his inability to throw at full strength following right labrum surgery. But Yoshida is up to speed offensively, and DH’d regularly for the Red Sox during Grapefruit League action. Yoshida would also give the Sox the left-handed bat they lost in Casas.

“I think it's important to decouple those things, just given that Masa has had some hurdles as it relates to recovering with the throwing, and we still feel like he's a capable outfielder and want to make sure that when back, he’s completely healthy,” said Breslow. “So I would try to keep those two things separate.”

What about the stud prospects?

If only Roman Anthony and Marcelo Mayer -- Boston’s No. 1 and No. 3 prospects per MLB Pipeline -- had experience playing first base. Both are left-handed hitters. Anthony is an outfielder and Mayer is a shortstop, though he did get work at second and third base during Spring Training and at Worcester at times this season.

“It doesn't seem like that's in the plans right now,” said Breslow. “I think both of those guys, obviously, are showing the ability to impact both sides of the ball. But given the bright futures that they have ahead of them at their respective positions, introducing additional variables doesn't make a ton of sense right now.”

What about Mayer or Anthony coming up and playing a natural position, with someone else on the roster moving to first base?

“I think we need to put all options on the table,” said Breslow. “Asking some guys who haven't played in the big leagues yet to assume new positions at the same time they're trying to make that transition is a difficult task. But we need to be open-minded about solutions here.”