"About 12 hours," Gyorko said Thursday.
Tests on Gyorko's right foot -- he's on the disabled list with plantar fasciitis -- showed not enough improvement to keep the cast and boot off.
"It's not a great sign," said Padres manager Bud Black.
On Thursday, the cast and protective boot went back on.
"It's similar to the first time. We're planning on waiting a week and then we'll look at it again," Gyorko said. "Until then, we're in a waiting pattern again."
The Padres placed the second baseman on the disabled list on June 6, retroactive to June 4. In terms of calling this a setback, Gyorko wasn't so sure -- mostly because there's no timetable, even a provisional one, that he or the Padres medical staff are using as a guide.
"It's so tricky and it varies," Gyorko said. "Each case is different. Knowing how long would make things a little easier."
Gyorko said surgery isn't an option at this point because tests have shown there's no tear in the foot. All he can do at this point it rest the foot and wait.
"I'm almost certain I'll play again [this season]," Gyorko said. "I'll be back at some point."
Corey Brock is a reporter for MLB.com. Keep track of @FollowThePadres on Twitter. Will Laws is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.