A lot needed to happen for Pittsburgh to clinch Mike Tomlin's fourth playoff season in his fifth year.

If not for field goals of 59 and 51 yards from Denver K Matt Prater, and a suffocating defensive performance in a Denver 13-10 (OT) win over Chicago, the Steelers would have qualified for the 2011 NFL Playoffs at the end of Week 14.

Along with Pittsburgh's win Thursday Night win over Cleveland, it needed losses from Cincinnati (20-19 to Houston), Tennessee (22-17 to New Orleans), Oakland (46-16 to Green Bay) and Denver. to return to the playoffs to defend its AFC Championship crown.

Despite being down 10-0 to Chicago with two minutes left in the game, Denver ensured the Steelers would have to wait at least another week to clinch. Prater drilled a 59-yard field goal at the end of regulation to send the game to overtime, and after Denver's defense recovered a Marion Barber fumble inside Broncos territory, QB Tim Tebow led the Broncos (8-5) to the game-winning field goal.

A win over San Francisco in Week 15 will put Pittsburgh in the postseason.

Houston defeated Cincinnati in dramatic fashion, as rookie QB T.J. Yates hit Kevin Walter for a 6-yard touchdown pass with two seconds remaining. Houston never led the game until its final two seconds.

With that, and Tennessee's loss, Houston clinched its first ever AFC South division championship, and will be in the playoffs for the first time in franchise history.

Tennessee lost QB Matt Hasselbeck in the first half, but rookie Jake Locker threw for 280 yards and a touchdown, and rushed for another score. The Titans had the ball at the Saints 5-yard line when Locker was sacked to end the game.

Oakland was on the wrong side of a thorough 46-16 whipping by Green Bay. The Packers led 31-0 at halftime, but the Raiders played considerably better in the second half, after turning the ball over four times (three Carson Palmer interceptions and a failed fake punt) in the first two quarters.