BALTIMORE — Thirdstring quarterback Dennis Dixon was doing a fine job for the Pittsburgh Steelers in his first NFL start—until he was forced to work overtime.

An interception by rookie Paul Kruger set up a 29-yard field goal by Billy Cundiff with 6:42 left in the extra session, giving the Baltimore Ravens a 20-17 victory Sunday night.

Dixon started because Ben Roethlisberger was sidelined with a concussion and backup Charlie Batch had a broken left wrist. Dixon had thrown only one pass in two seasons before getting the nod against the Ravens.

For much of the game, Dixon did his best impersonation of Roethlisberger. He threw a 33-yard touchdown pass to Santonio Holmes, and even added a personal touch, running for a 24-yard touchdown to put Pittsburgh up, 17-14, in the fourth quarter.

But in overtime, Dixon’s lone turnover provided the Ravens (6-5) a much-needed win and sent the Steelers (6-5) to their third straight defeat — their longest skid since a three-game run in 2006.

Kruger picked off the pass and returned it 26 yards to the Pittsburgh 28, and six plays later Cundiff delivered the gamewinner in Baltimore’s first overtime win since November 2005 — also against the Steelers.

Pittsburgh’s past two defeats have come in overtime. Dixon went 12 for 26 for 145 yards, and Rashard Mendenhall gained 95 yards on 24 carries.

Joe Flacco completed 23 of 35 passes for 289 yards and a touchdown to keep Baltimore in the thick of the playoff hunt.

The game was a rematch of last season’s AFC Championship Game, when the Steelers completed a three-game sweep of the Ravens with a 24-13 win.

With Roethlisberger in full uniform looking on from the sideline as the third quarterback, Dixon ran around the right end for a touchdown on a third-and-5 from the Baltimore 24 to give the Steelers their first lead, 17-14, with 6:24 left.

But the Ravens came back. Facing a fourth-and-5 from his own 46, Flacco completed a 44- yard pass to Ray Rice to set up a 24-yard field goal by Cundiff with 1:51 to go.

Rice ran for 88 yards on 19 carries and caught five passes for 67 yards.