Sandoval has struggled during his opportunities this season, slashing .212/.269/.354 and making five errors in 58 total chances. The Red Sox owe him the balance of his $17 million salary for this season, and he is on the books for $18 million annually in 2018-19. The Red Sox also have a $5 million buyout on Sandoval's $17 million option in '20.
"The unfortunate part is that you end up in a position that sometimes you have to make various decisions because of time frames that are involved," Red Sox president of baseball operations Dave Dombrowski said. "You've got disablements that become reinstatements. You have trading deadlines that can't be stretched any longer. So, you're forced into making decisions. I don't know what we're going to do.
"But I have no qualms that these guys have done a tremendous job for us. Really, it's a situation where they've played very well here at this point. Sometimes you're just forced into making decisions because of time frames."
Holt's ability to play first base could allow the Red Sox to option Sam Travis, a top prospect who has only been starting against lefties. That could allow Marrero or Lin to remain on the roster when Sandoval and Holt are ready to return.
Despite the contributions by Marrero and Lin, the Red Sox could also look to make upgrades at third base via a trade by the July 31 non-waiver deadline.
"They've stabilized the position is the best way to say it. Stabilized and provided some help for us," Dombrowski said. "But I think you're also in a spot that you're always cognizant of trying to help the club however you can. I don't want to just single that spot out. I am a believer that if you're going to do something to help your club, you need to do it by the 31st of July or August 1. Because after that, you don't control your own destiny."
Holt is finally turning the corner in his recovery from vertigo, which put him on the disabled list April 21. His Red Sox return will be significant given his ability to play seven positions and his left-handed bat.
"He's been pretty much symptom-free coming out of the games in which he's played," Red Sox manager John Farrell said. "So we'll get him on the infield a little bit more frequently while with [Triple-A] Pawtucket but the way he's tracked the baseball at the plate, the way he's moved defensively, it's all been moving in a positive direction."
As for how the roster will shake out within the next couple of weeks, the Red Sox will make that evaluation as best they can when the time comes.
"Those two guys as we've talked about repeatedly for the past three or four, five days, they've done a fantastic job," Farrell said. "Tzu-Wei and Deven have been very good and I think when you have good players that are performing well, those are the type of decisions you want. You want difficult decisions.
"That's a testament to our depth. Some of it may be a pleasant surprise, particularly in Linnie's case. So, you know, we've got these first two games to take care of before we go to the break and we'll take care of the decisions when they come about."