I had to pick a song reference that wasn’t “London Calling.” I love the tune, but it’s borderline played out.

The 49ers ruled Alex Smith out of Sunday’s game against the Broncos overseas. Smith sustained a separated shoulder in Week 7 against the Panthers and will be unavailable for the game. David Carr entered the contest and did nothing to impress embattled coach Mike Singletary. As such, former Baltimore quarterback and Heisman Trophy winner, Troy Smith, will get the nod.

Smith hasn’t started a game in three seasons, and lost his last opportunity to challenge for the starting gig in Baltimore when he was sidelined for much of the 2008 training camp schedule because of an illness. Joe Flacco stepped into the role and never looked back.

He has familiarity with former Ohio State teammate Ted Ginn, Jr., but all eyes will be on Smith’s ability to connect with Vernon Davis and Michael Crabtree downfield.

I’m intrigued. OK, so it’s probably the Big 10 loyalist in me. Still, the offense has to come alive sometime … right?