Nobody counted on the play of second-year quarterback Dennis Dixon making things interesting.
Dixon, making his first career start, ran for one touchdown and threw for another.
It was his first mistake, however, that did the Steelers in.
Dixon was intercepted by rookie Paul Kruger on third-and-five from midfield in overtime and Kruger returned the ball to the Pittsburgh 28 to set up a 29-yard field goal by Billy Cundiff that lifted Baltimore to a 20-17 victory.
For four quarters, Dixon looked like a veteran. He threw for 145 yards and a touchdown and also ran for a score with 6:32 left in the game to give the Steelers (6-5) their first lead.
"I liked his demeanor throughout it all. He made some plays," Steelers Coach Mike Tomlin said. "I thought he represented himself relatively well."
Dixon's touchdown was a designed running play. He faked a handoff to wide receiver Mike Wallace and spun around right end, picking up a block from running back Mewelde Moore to go untouched on the 24-yard run.
But Baltimore (6-5) answered on its next possession, despite being backed up to third-and-22 with just over four minutes remaining.
Joe Flacco threw a 17-yard completion on third down, putting the Ravens in a fourth-and-five situation. Coach John Harbaugh initially indicated he would punt to the Steelers, but called a timeout and went for the first down. Flacco threw a short pass to running back Ray Rice, who broke three tackles for a 44-yard gain to the Pittsburgh 10.
That set up a 24-yard field goal by Cundiff that tied that game, 17-17, with 1:51 remaining in the fourth quarter.
The Steelers were forced to punt after running just three plays and the Ravens used a pass interference penalty against Ike Taylor to put the ball at the Pittsburgh 35 with 54 seconds remaining.
But the Steelers' defense held and Cundiff's 56-yard field goal attempt as time expired fell short.
The Steelers used a strong rushing attack to protect the young quarterback, who came into the game having thrown just one NFL pass. The Steelers ran the ball 38 times for 153 yards, 95 of which were gained by Rashard Mendenhall on 24 carries.
But Flacco's experience over Dixon was obvious. Flacco completed 23 of 35 passes for 289 yards and a touchdown despite being sacked five times.
The Ravens scored on their opening possession after holding the Steelers to a three-and-out.
Flacco completed all five of his passes and Willis McGahee finished the drive with a two-yard TD run to put Baltimore ahead, 7-0.
The Steelers answered, however, early in the second quarter as Dixon threw his first career touchdown pass, a 33-yarder to Santonio Holmes off of a play-action fake to tie the game at 7-7.
After completing the fake to Willie Parker, Dixon rolled to his right and threw a perfect pass over the middle to Holmes, who outraced cornerback Dominique Foxworth the final 15 yards to the end zone.
But Baltimore took a 14-7 lead late in the first half, as Flacco completed a 59-yard bomb to Mark Clayton, then tossed a 10-yard TD pass to Derrick Mason on a fade over Ike Taylor with 1:45 remaining in the second quarter.
The Steelers used good field position to trim the lead to 14-10 with 9:09 remaining in the third quarter on a 44-yard Jeff Reed field goal.
A sack by Travis Kirschke pinned the Ravens back deep in their own territory and Stefan Logan returned a Sam Koch punt to the 50. Mendenhall picked up 20 yards on a short pass from Dixon to put the Steelers in field goal range.
Despite the closeness of the loss while playing with his third-string quarterback, Tomlin was obviously fired up after suffering the first three-game losing streak of his career.
"We will not go gently," Tomlin said. "We won't go in a shell. We're going to go into attack mode, because that's what's required."