Utah will try to match its best home start in four seasons when it takes on the Raptors, who are looking to end an eight-game road losing streak.
Jefferson poured in a season-high 31 points and grabbed 15 rebounds to help the Jazz (10-10) end a three-game skid with Wednesday's 87-81 home win over Orlando, but he had to be helped off the floor in the final minutes due to back spasms.
Jefferson said after the game that he'd be ready for Friday, but Corbin was unsure of that prior to Thursday's practice.
Favors, averaging 9.3 points and 7.5 rebounds, is also a game-time decision after missing the previous three contests with plantar fasciitis in his right foot.
"It would be interesting (if both can't play), but we still feel good about the bigs that we have," Corbin said. "We're logjammed there, so it would be an opportunity to get (others) some minutes on the floor."
Corbin mentioned that little-used Jeremy Evans could log some minutes and Marvin Williams, who returned Wednesday after sitting out three games with concussion-like symptoms, could spell Paul Millsap at the power forward spot as the Jazz look to improve to 8-1 at home.
A makeshift frontline would seem to benefit the Raptors (4-15), who have been outrebounded 100-77 on the first two stops of a five-game trip.
Toronto gave up 56 points in the paint in Wednesday's 107-100 loss to Sacramento, and the Raptors are allowing an average of 108.0 points in the last six games.
Toronto hasn't dropped nine in a row on the road since a 14-game skid Jan. 7-March 16, 2011.
"You can't explain in words how frustrating it is," said swingman DeMar DeRozan, who matched a career high with 37 points in a 140-133 triple-overtime home loss to Utah on Nov. 12. "We try to work as hard as we can, but the ball doesn't bounce our way, the ball doesn't go in when you need it to go in. It's everything you can think of."
The Raptors probably thought they were on their way to a victory over Utah last month as they led by 11 with seven minutes left, but the Jazz rallied behind 34 points from Millsap and 24 and 17 boards from Jefferson.
Raptors point guard Kyle Lowry missed that contest with a sprained right ankle, but he'll be ready to go after scoring 29 of his season-high 34 points in the second half Wednesday.
In its last visit to Salt Lake City, Toronto ended a 12-game skid in this series with a 111-106 double-OT win Jan. 25. Jefferson missed that game with an inflamed right ankle.