Ben Roethlisberger ruled out for the Pittsburgh Steelers; Byron Leftwich to start against Ravens

Pittsburgh Steelers quarterback Ben Roethlisberger will not play in Sunday night's pivotal AFC North showdown with the Baltimore Ravens, Jay Glazer of FOXSports.com reports.

[Photo gallery: Quarterbacks hurt in Week 10]

Roethlisberger suffered a sprain to the sternoclavicular joint, which connects the sternum to the collarbone, and a rib injury when he was sacked by Kansas City Chiefs linebacker Justin Houston on the third play of the third quarter in the Steelers' 16-13 overtime win on Monday night. Roethlisberger, along with his wife, left the stadium for further medical testing at a local hospital.

According to Ed Bouchette of the Pittsburgh Post-Gazette, the rib injury is the real problem -- were Roethlisberger to play before that injury heals, he could actually risk death if a rib presses aganst his aorta.

On Tuesday, Steelers head coach Mike Tomlin said Roethlisberger was "questionable" for the Ravens game. Per Bouchette, Roethlisberger was undergoing more medical testing on Tuesday and was more likely to be out indefinitely than play this week against the Ravens.

The Steelers have confirmed the report, with the team's official website reporting that Byron Leftwich would start on Sunday night against the Ravens.

Leftwich completed 7 of 14 pass attempts for 73 yards in relief work on Monday night. Leftwich has not started an NFL game since Sept. 27, 2009, when, as a member of the Tampa Bay Buccaneers, he completed 7 of 16 passes for 22 yards and an interception in a 24-0 loss to the New York Giants. On the day after that performance, Leftwich was benched in favor of Josh Johnson, who was most recently the quarterback of the Sacramento Mountain Lions in the United Football League before that league ceased operations last month.

[Related: ESPN touts Ben Roethlisberger's 'drink and drunk' style]

Acquired from the Buccaneers in 2010, Leftwich made one appearance in relief of Roethlisberger that season — garbage time in a 41-9 win over the Cleveland Browns in the regular-season finale — and spent the 2011 season on injured reserve after breaking his left arm when he landed awkwardly while scrambling for a first down in a preseason game against the Atlanta Falcons.

With Leftwich moving up to the starting role, veteran Charlie Batch moves up to the No. 2 spot on the depth chart. Carrying three quarterbacks on the 53-man roster means the Steelers are not carrying an additional arm on the practice squad. If they were considering adding one, either to the active roster or practice squad, there are options available. Jerrod Johnson went to training camp with the Steelers and posted a passer rating of 136.2 before the 6-foot-5, 250-pounder from Texas A&M was released as part of the team's final roster cuts. Johnson replaced the aforementioned Josh Johnson as the Sacramento Mountain Lions starting quarterback this season and has practice squad eligibility remaining.

The Steelers could also turn to a veteran to keep on the 53-man roster. As luck would have it, in the wake of injuries to Roethlisberger, and concussions suffered by Michael Vick, Alex Smith and Jay Cutler, ESPN's Adam Schefter reported that Al Irby, the agent for free-agent quarterback David Garrard, disclosed that his client was cleared to begin working out for NFL teams on Tuesday.

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