**UPDATE** I’m told Luke Marquardt re-fractured the same foot that kept him out of the 2012 season at Azusa Pacific and the 2013 season with the 49ers. Marquardt suffered the injury in practice, will have surgery on the foot and will revert to injured reserve. The 49ers will have an extra spot on their 90-man roster. The 15 players that are trying out this weekend will get the first shot at the opening.
The 49ers released offensive tackle Luke Marquardt, an undrafted free agent a year ago who spent the 2013 season recovering from a foot injury, a league source said. Marquardt was eligible to take part in the team’s ongoing rookie minicamp but was not on hand today.
The only player listed as an offensive tackle at the minicamp is Carter Bykowski, a seventh-round pick a year ago who spent 2013 on the practice squad. Fou Fonoti, who is listed as a guard, played tackle at Michigan State. Fonoti is an undrafted rookie.
Marquardt was intriguing because of his size -- 6-8, 315 pounds -- long arms (34 1/2 inches) and athleticism. However, he played at a small school, Azusa Pacific, and missed the 2012 season there with the same foot injury that sidelined him in 2013.