But they know for sure that quarterback Chad Henne will be taking the snaps.
Coach Gus Bradley said Monday that Shorts could play against the Chargers despite suffering an injury to the sternoclavicular joint in his right shoulder early in the Jaguars' 35-19 loss to the Denver Broncos on Sunday. Shorts was injured on the third offensive snap when he hit the ground after an incomplete pass.
"He's sore now, and there's a lot of swelling in there," Bradley said. "We'll know more in a couple days. The good news is the joint is stable."
Starting quarterback Blaine Gabbert will miss a second consecutive game because of a left hamstring strain. Henne, who threw for 303 yards and two interceptions against the Broncos, will make his second consecutive start and fourth this season.
Bradley said Gabbert's injury could keep him out even longer than this Sunday. The Jaguars play the San Francisco 49ers in London on Oct. 27 and have a bye the following week.
"Blaine will throw on the side [this week]," Bradley said. "We'll see where it is. It is an injury that may take a couple weeks. We'll get him to start throwing on the side. We'll see when Blaine comes back but right now Chad is our quarterback for the San Diego game."
Shorts left the stadium Sunday night with his arm in a sling but wasn't using the sling Monday because he'd rather deal with the pain than immobilize his arm.
"I'm not a sling guy," he said. "I'm not going to walk around looking handicapped when I'm not handicapped. Maurice Jones-Drew always talks about being a pain freak, and I kind of like the pain. I'm not going to be walking around being slinged up about it."
Shorts, who leads the Jaguars (0-6) with 31 catches for 411 yards, said he is in a lot of pain but is going to try to play Sunday.
"My goal is to get out there and play this week," Shorts said. "If I can't, I can't. … We'll see what happens as the week goes on."
Bradley also said receiver Justin Blackmon, who caught 14 passes for 190 yards against the Broncos, suffered minor groin and hamstring injuries and likely will be held out of practice Wednesday. Bradley said Blackmon will be able to play against San Diego.