The Colts released their injury report after coach Chuck Pagano said Luck was a full participant in practice Friday.
The shoulder issue caused Luck to miss practice Wednesday and to be limited Thursday.
"I think everybody is trying to read too much into this," Pagano said Friday. "... We're going to manage him the way we manage all our players and try to get him to Sunday as healthy as possible."
Luck's health has and will continue to be an important matter after he missed nine games due to injury last season. He described his shoulder as being sore when he last addressed the media on Wednesday.
Luck was hit a total of 16 times -- five sacks and 11 hits -- during their Week 2 loss to the Denver Broncos.
"[It] was a physical game," Luck said.
Luck and offensive coordinator Rob Chudzinski both said during the week that they expect the quarterback to start when the winless Colts (0-2) play San Diego on Sunday.
Scott Tolzien will start if Luck is ruled out against the Chargers.