Joseph suffered a torn patellar tendon on a play near the end of the first half. He will have surgery on Monday, Schiano said, and the team will place him on injured reserve.
"Thanks for all of the support, positive vibes, and prayers," Joseph wrote on Twitter. "Overall, it could be worse. God has a plan. I'll be back ASAP."
The Bucs had hoped to pair Joseph with free-agent pickup Carl Nicks to form one of the league's top guard tandems. But they'll now have to look at other options.
"It's part of what we do," Schiano said. "You mourn and you move on."
Schiano said the Bucs will monitor available guards, but he thinks Joseph's replacement in the starting lineup could come from within. Ted Larsen replaced Joseph on Friday night and could be the leading candidate. The Bucs also have liked what they've seen from Derek Hardman in the preseason.