Ben Roethlisberger is sacked by Chiefs LB Tamba Hali in the third quarter Monday night. Roethlisberger left the game with a right shoulder injury. (AP)

The Steelers lost franchise quarterback Ben Roethlisberger for most of two quarters and maybe longer -- a week? a month? -- with a right shoulder injury, so their 16-13 overtime victory over Kansas City on Monday night came at a price.

Roethlisberger suffered a sprained right shoulder, the team announced Tuesday. As of now, his status for Sunday's game against the Baltimore Ravens is questionable. Steelers coach Mike Tomlin said Roethlisberger suffered a sprained SC joint, which connects the sternum to the collarbone.

“He's being evaluated,” Tomlin said. “Obviously this injury puts his participation in the questionable category for this week. I'll have more information as this week unfolds.”

CBS Sports' Jason La Canfora reported that the team is expecting Roethlisberger to be out for multiple games.

Another Pro Bowl player, team-leading tackler Ryan Clark, was lost to an apparent concussion -- though he reported afterward that he was fine -- for the second time in three games after seeming to sustain one.

Add safety Troy Polamalu, wide receiver Antonio Brown, running back Rashard Mendenhall and offensive tackle Marcus Gilbert to that star-studded injury list, and the Steelers (6-3) were sans four Pro Bowl players and six starters/difference-makers by late Monday in Heinz Field. And they may well miss them a while longer, which is inopportune timing with Baltimore looming twice in the next three weeks.

Coach Mike Tomlin oft repeats his next-man-up mantra that “the standard is the standard,” but it’s difficult to maintain such a high bar with jayvees sprinkling your varsity. Especially at important skill positions absent Pro Bowlers.

It explains the Steelers' vexing night against Kansas City (1-8). It portends somewhat ominously for their AFC North future against Baltimore on Sunday, then at Cleveland, at Baltimore and a finish with five of their final seven regular-season games inside their division.

Offense: C-

The Steelers passed for their fewest yards this season, amassed their fewest offensive yards this season and rushed for their fewest in what had been a strong four-game stretch on the ground. It never helps when your $100 million quarterback injures his right, throwing shoulder and leaves the stadium in a sling. Yet Roethlisberger already was experiencing a trying night, with his receivers being separated from balls or merely failing to catch accurate passes. In all, the Steelers’ receivers caught six of the 19 passes on which they were the targets. The only touchdown they did muster came from WR Mike Wallace’s knees and body, falling and enveloping a Roethlisberger fade-pattern pass in the end zone. The offensive line, after moving the Bengals, Redskins and Giants defenses with some ease, struggled against the Chiefs -- who, undoubtedly, had a good read on the playbook of their former coach, Todd Haley. You wouldn’t expect QB Byron Leftwich to be so sharp on eight games’ rest and one season (2011) off due to injury since he last played in the 2010 finale. Rather, everybody else but him showed rust Monday. Previous game’s grade: A

Defense: C-

Quarterback Matt Cassel went 11 for 26 and got sacked twice. The Chiefs converted just 2 of 15 third downs, and those came in a back-to-back spurt that lead to a missed 33-yard field-goal attempt. Still, the Steelers’ defense labored a good bit of the night. The Steelers fell behind 10-0. Chiefs RB Jamal Charles became the second 100-yard rusher of the season against them, after fellow AFC West young gun Darren McFadden of Oakland. The Chiefs averaged 4.1 yards per rush, tied for the third-most in the past eight Steelers games alone. The front seven blamed it on cut blocking and more Chiefs talent than a 1-8 record indicates, yet still it remains a stunning trend for a team that for so long squashed the run. Apparently, the 3.1-yard average by the stumbling Giants a week earlier was the exception rather than the norm. Next for the Steelers’ defense comes Ray Rice, rookie Trent Richardson and Rice again in a running row. Previous game’s grade: A+

Special teams: B

Pro Bowl returner Brown was absent due to a high-ankle sprain that many think could be serious, and rookie Chris Rainey played with achy ribs from a week earlier. So the return game was peppered with a David Gilreath who was signed off the practice squad 4½ hours before kickoff. The previously sketchy special teams did nothing to hurt the Steelers on a trying Monday night, but they did nothing to rescue them when they needed it, either. Previous game’s grade: A

Coaching: C-

Besides Haley’s offensive plan and play calling that did little to unnerve the Chiefs' defense, the coaching on Monday needed to fall on the motivational/emotional balance more than the strategic side. And therein is where Tomlin’s talents normally show. However, the Steelers were off kilter throughout the evening and failed to possess anywhere near the spark that, well, got the Chiefs in trouble: two penalized celebrations for touchdowns that weren’t, all within an eight-snap, 2-minute, 17-second forgettable time in the third quarter. Guard Willie Colon suggested that because of the shortened week, the coaches may not even review Monday’s game film with the players Tuesday. Good thing. It might scare them too much. Previous game’s grade: B+

Follow Steelers reporter Chuck Finder on Twitter @CBSSteelers and @cfinder.