Curtis would replace rookie Jeremy Maclin, who reinjured his left foot during last Sunday night's 45-38 victory over the New York Giants and might be out for two weeks or more.
Maclin left in the first quarter with torn tissue in the bottom of his foot. He exited Giants Stadium on crutches after the game.
Maclin, the Eagles' first-round draft pick out of Missouri, is second on the team with 46 receptions for 623 yards and four touchdowns. He originally injured the foot during a Dec. 6 victory over the Atlanta Falcons, and he missed practice Wednesday and Thursday leading up to the Giants game, but he was back on the field Friday and started Sunday night.
The veteran wideout said he believed he could go Sunday night. Now he might have the chance against the 49ers.
"We'll see how Kevin is," Reid said. "He really took quite a few reps, more reps than I thought he would last week. So that will be increased this week, and we'll just see how he does. If he's not right, he's not right, and we'll work from there.
"He said he felt pretty good. His legs were tired and his wind wasn't where he wants it to be, but he actually felt pretty good."
Curtis, who had surgery for a sports hernia during the offseason, caught five passes for 70 yards in the two games that he played before the knee injury.
"I'm stating the obvious here, but DeSean is playing at a very high level," Reid said. "The thing I appreciate about him the most is he loves to play the game. He gets very excited. He doesn't care how big the game is or anything else. He just goes out and plays and enjoys doing it."
Copyright 2009 by The Associated Press