Robinson, an undrafted rookie out of Notre Dame in 2012, was on the Cincinnati Bengals practice squad after playing the past two seasons with the team.
The Chargers will be starting their fourth center of the season this week against the Oakland Raiders. Starter Nick Hardwick, who has played his entire 11-year career in San Diego, injured his neck in Week 1 and was ruled out for the season. Rich Ohrnberger injured his back while filling in for Hardwick and has missed the past two weeks, but is expected to return this season. Doug Legursky injured his knee on Sunday against the Jets and is out for the season. Rookie third-round pick Chris Watt is expected to start in Week 6.
Robinson hosted Watt when he visited Notre Dame as a high school recruit, Gehlken reports.
"He did a good job of getting me ready," Watt said. "I'll try to get him caught up as fast as possible." "Trevor's a smart guy, too," Watt said. "He'll figure out what to do really quick."
Despite the turnover at center, the Chargers have opened the season 4-1. San Diego is 11th in the NFL in yards per game and eighth in points per game.
The Chargers travel to Oakland to play the Raiders on Sunday at 4:05 p.m. ET.
- Paul Palladino