One day later, tight end Vernon Davis' much-debated near-catch in the third quarter Sunday still shadowed the 49ers - and not only because they disagreed with the referee's ruling. Davis sprained the medial collateral ligament in his right knee on the play, an MRI exam revealed Monday. He probably will miss the next two games, the team announced, removing a key option from an offense already struggling to reach the end zone. Davis caught four passes for 56 yards in Sunday's 37-16 loss to Pittsburgh, in the first game after he requested a more prominent role in the offense. Now, as the 49ers prepare for home games against Seattle and Baltimore the next two weeks, Davis' injury temporarily leaves him with no role in the offense. Backups Delanie Walker (the better receiver) and Billy Bajema (more of a blocker) figure to share tight-end duties in Davis' absence.