Betts suffered a contusion on the play because of the way he landed. He also received a couple of small cuts on his face. The timeline on his possible return is uncertain.
"Obviously the impact of the wall and also when he landed," Boston manager John Farrell said, "there was a little bit of a twisting effect where he's got a sprain in the back. X-rays were negative. He's a little sore right now."
Farrell said that Betts did not exhibit any concussion-like symptoms.
"All those tests were done here at the ballpark," Farrell said. "He took quite an impact, obviously. The facial abrasions, those are very minor."
Betts finished out the half-inning after being checked on by Farrell and the training staff. Alejandro De Aza pinch-hit for Betts later in the second and took over in right field in the third, with Rusney Castillo moving from right to center.
"I didn't really see the whole thing unravel. Went back and looked. It didn't look too good at all," said Red Sox starter Joe Kelly, who was pitching at the time. "We're all hoping he's OK, and that it's just a little sprain and nothing more."
Betts hit a solo home run in his only at-bat during Boston's five-run outburst in the first, snapping a stretch of 33 games without one.
Alec Shirkey is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.