Tanner Houck is likely to rejoin the Red Sox starting rotation, which would probably push Garrett Richards to the bullpen. Charles Krupa/Associated Press

The Red Sox appear to be on the verge of a massive shakeup to their struggling starting rotation.

With a 26th-ranked 5.43 ERA from their starters since the All-Star break, the Sox could use the change.

Manager Alex Cora said before Tuesday’s series-opener with the Rays that Nathan Eovaldi will start on Wednesday and Chris Sale will start on Saturday, but named no other starters for the rest of the week.

“Beyond that, we’re going to have a few conversations here in the clubhouse, being able to see everybody, we’ll talk to people and we’ll make an announcement probably after the game or (Wednesday),” Cora said.

The Rays are a team that statistically performs much worse against lefties than against righties, but the Sox chose not to bring back Sale on regular rest for Thursday’s series finale, and instead are giving him six days rest as he starts Saturday against the Orioles.

Otherwise, it would appear that Tuesday’s starter Eduardo Rodriguez would stay in the rotation with Eovaldi and Sale. Tanner Houck is also expected to rejoin the rotation soon.

If they stick to a five-man group, Nick Pivetta is the obvious choice to continue starting while Garrett Richards could join Martin Perez in the bullpen, though no announcement has been made.

AFTER STARTING THE year 4-0 against the Rays, the Sox have lost five straight to their division rivals. They’ve fallen to a season-low four games back in the American League East.

“Not surprisingly, they’re playing good baseball,” Cora said. “They’re doing a lot of good things with the pitching staff. It seems like they have a different set of relievers every 15 days. That’s what they are as an organization. You’ve got to praise that. At the same time, with everything going with us for the last 20 days or 10 days, however you want to see it, we’re still in a good position to win the division, to fight for the division or make it to the playoffs.

“Our goal is to win the division. It’s a big series. But if you think back to April 5 it was a big series too on April 5. That’s the way I see things. I try to look at something positive out of the negative and we’ll be ready to play against a tough team.”

INJURY UPDATES: Hirokazu Sawamura appears to have avoided a serious elbow injury.

The deceptive right-hander left Sunday’s game after throwing just three strikes and nine balls. He walked two and threw two wild pitches before exiting with elbow tightness.

“I didn’t like his body language,” Cora said. “I didn’t like the way he was throwing the ball. Usually, when you’re hurt, the first thing you lose is command. But he got treatment that night, got treatment (Monday), got treatment today, and everything that I’m hearing, especially from him, is that he’s OK.”

Christian Arroyo (hamstring) went through a full workout at Fenway Park and will take batting practice Wednesday before the Sox ramp him up for a rehab assignment sometime next week.
Danny Santana (groin) is one day behind Arroyo.

Kyle Schwarber (groin, hamstring) has recovered from the groin tightness but is still dealing with hamstring issues.

“He’s been running the bases and doing everything,” Cora said. “I’m not going to give you a day. We never do that. But he feels good and is feeling much better today than over the weekend.”

Alex Verdugo is still on paternity leave and will likely rejoin the team on Wednesday night.

“One thing for sure, he’s a happy camper,” Cora said. “We’re very proud of him. Everybody’s healthy. He got there five minutes before (his baby was born). He was able to be there, which is great.”

WITH BENCH COACH Will Venable (positive for COVID-19) and first base coach Tom Goodwin (close contact) stuck in Canada for a 14-day quarantine period, the Sox will add minor league coordinators Andy Fox and Darren Fenster to the big league coaching staff on a temporary basis.

Fenster just returned from Tokyo where he helped coach Team USA to a silver medal.

“I don’t know if the coaches get the medal, but hopefully he did and he can bring it here and we can see it,” Cora said.

Jason Varitek and Ramon Vazquez will help in expanded roles for the time being.