Scott said after the game the injury happened on a checked swing during his at-bat in the ninth. As he left the batter's box on a lineout to left field, he felt his back tighten up.
"It's frustrating but I believe in my faith that I'll have a good report tomorrow and that everything will be all right," Scott said.
Scott was forced to go to the 15-day disabled list in June because of back problems but said his current injury is unrelated.
"It's completely different," Scott said. "This is much less. I'm believing it's going to be something minor."
Matsui was 0-for-2 at the plate in relief of Scott.
Rays manager Joe Maddon said after the game that he didn't know the severity of the injury and would see how Scott feels Saturday.
Scott said his goal is to be ready by Sunday when Tampa Bay faces right-hander Blake Beavan.
Greg Zeck is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.