San Francisco 49ers starting right guard Dominick Puni exited Saturday’s pre-season matchup against the Las Vegas Raiders at Allegiant Stadium with a knee injury and was ruled out for the remainder of the contest, the team said. Puni’s absence leaves San Francisco without both of its first-string veteran guards. Ben Bartch is already sidelined by an elbow injury, forcing the club to rely on rookie Connor Colby, who started at left guard and could be moved to the right side depending on Puni’s recovery timeline. Running back Patrick Taylor was listed as questionable after suffering a shoulder issue, adding to the 49ers’ depth concerns as they prepare for the regular season. The club has not yet provided a timetable for Puni’s return.