Ben Roethlisberger delivered a masterful performance to help his Pittsburgh Steelers beat the Cincinnati Bengals 31-17 and advance to the second round of the playoffs yesterday, but a serious knee injury to Carson Palmer deprived fans of the opportunity to see a duel between two of the NFL’s best young quarterbacks.

The always efficient Roethlisberger had one of his most impressive games, throwing mostly short passes, finding gaps in the Cincinnati defense, spreading the ball around to seven different receivers, and finishing 14-of-19 for 208 yards and three touchdowns. Most important, Roethlisberger did not throw an interception against the Bengals, who picked off more passes than any other defense this year.

Roethlisberger was most effective when exploiting the coverage problems that Cincinnati’s linebackers had. He threw a touchdown pass to running back Willie Parker in the second quarter on a well-designed play on which Parker pretended to miss a block on Cincinnati linebacker Brian Simmons, allowed Simmons to blitz Roethlisberger, then ran into the area Simmons had vacated. Parker caught Roethlisberger’s soft throw and easily ran into the end zone.

Roethlisberger threw long balls just often enough to keep Cincinnati’s defense honest, finding receiver Cedric Wilson on two deep passes. Wilson beat Bengals safety Kevin Kaesviharn for a 54-yard reception early in the game, and the Steelers fooled the entire Bengals defense on a third-quarter trick play when Roethlisberger gave the ball to receiver Antwan Randle El, who ran to the right and tossed the ball back to Roethlisberger,who passed to a wide-open Wilson for a 43-yard touchdown.

Steelers running back Jerome Bettis, who is expected to retire at the end of the season, showed that he still has some gas left in the tank, carrying 10 times for 52 yards, including a five-yard touchdown on which he ran through the arms of Cincinnati defensive backs Tory James and Ifeanyi Ohalete. That run gave Steelers a 21-17 they would never relinquish.

As great as Roethlisberger was, Palmer will be the quarterback most people talk about today. He tore the anterior cruciate ligament in his left knee when Steelers defensive end Kimo Von Oelhoffen fell into him on his first pass, a 66-yard completion to rookie receiver Chris Henry. Palmer was carted off the field and won’t be ready to play until training camp in July, at the earliest. (Henry was also hurt and lost for the game on the play.)

Jon Kitna took Palmer’s place, and Cincinnati didn’t appear to change its offensive game plan in any way. Kitna is an experienced player, with 79 career starts, and has been billed as the best backup quarterback in the league, but he’s nowhere near as good as Palmer, and the Bengals’ offense struggled.

Kitna finished 24-of-40 for 197 yards, one touchdown, and two interceptions. Kitna becomes a free agent when the playoffs end, and if he had led Cincinnati to a playoff win, he could have earned himself millions. Instead, it’s unlikely he will get any offers to become a starter next year, and he will certainly not receive a big contract offer from the Bengals, who signed Palmer to a contract extension two weeks ago that included a $15 million signing bonus and ties him to the team through 2014.

In addition to keeping Kitna in check, Pittsburgh’s defense held Cincinnati to only 84 yards on the ground. Safety Troy Polamalu made several big plays, with four tackles, half a sack, and an interception. But he also helped set up a Cincinnati touchdown with an unsportsmanlike conduct penalty that gave the Bengals a first down after they had been stuffed on third down.

Pittsburgh will need more of those big defensive plays and fewer of the dumb penalties if it’s going to have a chance to win next weekend in Indianapolis. In November, Indianapolis crushed Pittsburgh 26-7 in a game the Colts dominated from the opening whistle.

Everyone knows that slowing down the Colts’ offensive attack of Peyton Manning and Edgerrin James is key to beating the Colts, but what hurt Pittsburgh most when it played Indianapolis previously was the way the Colts shut down the Steelers’ running attack. Pittsburgh’s ground game is strong and physical, while Indianapolis’s run defense is small and vulnerable. But when they played in November, the Steelers’ three running backs managed only 58 yards on 21 carries. They’ll need a better effort to have a chance of pulling the upset.

For a Bengals team making its first playoff appearance in 15 years, a season of optimism suddenly looks a lot less positive. Palmer doesn’t rely much on his mobility, so a knee injury doesn’t necessarily have serious long-term implications for his career. But that $15 million signing bonus ensures he is the Bengals’ franchise player, and Cincinnati fans will be holding their breath until they know that he’s ready to return.

Mr. Smith is a regular writer for FootballOutsiders.com.