ST. PETERSBURG, Fla. — A marquee pitching matchup between Charlie Morton and David Price was overshadowed by the MLB rulebook.

Morton struck out 11 over seven innings and the Tampa Bay Rays avoided a three-game sweep by beating Price and Boston 3-2 in a game the Red Sox protested on Wednesday.

Confusion reigned in the top of the eighth inning when a series of defensive changes involving reliever Adam Kolarek prompted Boston Manager Alex Cora to protest the game due to the placement of subs into the Rays lineup after the designated hitter was removed.

Umpire crew chief Angel Hernandez, through a pool reporter, said Rays Manager Kevin Cash did not specify where Kolarek and the others would be placed in the lineup and that by rule it became his decision.

“In case the manager fails or refuses to make the decision, the plate umpire is authorized to decide the necessary batting order,” Hernandez said. “The umpire’s decision is final.”

Kolarek replaced Morton and retired pinch-hitter Sam Travis on a pop fly. The left-hander then shifted to first base when Cash brought in reliever Chaz Roe, who got a fly ball from Mookie Betts.

After Kolarek then returned to the mound and Nate Lowe entered to play first base, Cora met with the umpires, which prompted around a 15-minute stoppage as the umpires discussed the matter.

After the protest was made and the game resumed, Kolarek got a first-pitch grounder from Rafael Devers.

During the lineup changes, Cora argued that Kolarek should have been placed ninth in the Rays batting order since he was replacing Ji-Man Choi at first base.

However, Kolarek was placed in the third spot, replacing designated hitter Austin Meadows, while Lowe went into the nine hole. Cora maintained that since Kolarek had replaced Choi, the Rays still had a DH in the game and there was only one lineup spot in which to place Kolarek.

“The pitcher moved to a position and we felt there were some illegal substitutions,” Cora said. “It was a mess, and I wasn’t even able to keep up with Angel. So we protested the game, and we’ll see where it goes.”

An unhappy Cora again talked with the umpires after the third out, which delayed the start of the bottom of the eighth.

“There appeared to be some confusion, but I’m confident we got it right at the end of the day,” Cash said. “Obviously, it’s not customary what took place.”

Morton (12-3) allowed two runs and five hits in lowering his AL-best ERA from 2.61 to 2.60.

“I don’t think I made a ton of great pitches,” Morton said. “Obviously I was able to make some good ones, and I thought we played well defensively.”

Emilio Pagán pitched the ninth for his seventh save.

Price (7-4) went six innings, giving up three runs, four hits and two walks while striking out eight.

The Red Sox slipped back into third place in the AL East as they face the Yankees in a pair of key four-game series on consecutive weekends.

Tampa Bay took a 3-2 lead in the fifth when left-handed hitting Joey Wendle, who got the start at shortstop in place of slumping Willy Adames, lined an RBI single to center off Price and scored on Guillermo Heredia’s double.

“The way he (Morton) has thrown the baseball all season long, that’s very impressive,” Price said. “Knowing you’re going against him and you get staked to an early two-run lead, to give that up and give up those three runs in the fourth and fifth inning, that was tough.”

Tommy Pham got the Rays’ first hit on a homer leading off the fourth.

Devers put the Red Sox up 2-0 with a well-placed opposite-field single in the third. He has 29 RBI this month.

Brock Holt flared a single to left and went to third on Betts’ double. Both scored when Devers beat an infield-in shift by slapping his hit through the vacated shortstop position.

Morton retired 14 of his final 15 batters after Devers’ single.

NOTES: Cash said CF Kevin Kiermaier (sprained left thumb) will need a short minor league rehab assignment before returning. The defensive standout, hurt last Saturday diving head first into first base on an infield single, is hopeful of being back in the next couple of weeks. … Reliever Jose Alvarado (right oblique strain) expects to have his first bullpen session next week.