The San Francisco 49ers are looking pretty terrible against the Cleveland Browns, and any chance for a comeback will have to happen without their left guard. Alex Boone went down with a leg injury in the third quarter, and has been ruled out with a knee injury.
The 49ers inserted Marcus Martin in at left guard when Boone went down. Martin started the day at center, but the team has been rotating him with Daniel Kilgore. Boone suffered his injury during a Kilgore series, and that resulted in moving Martin in at left guard.
There is no word on the severity of the injury beyond today's game, but Jim Tomsula will get plenty of questions about it in his post-game press conference, and then again during his Monday day-after press conference. Boone likely will get an MRI to look for any structural damage. That would happen sometime on Monday, so any further word likely would not come until sometime on Monday.