But Roethlisberger and Parker responded well to their early miscues, helping the Steelers to a 27-13 victory here at Heinz Field over the Eagles.
Roethlisberger, seeing his most extensive playing time of the preseason, threw an ill- advised pass that was intercepted on Pittsburgh's opening possession, but recovered to complete 13 of 25 passes for 247 yards in leading the Steelers to a 13-3 halftime lead.
Parker, meanwhile, lost a fumble at the Eagles' goal line on Pittsburgh's third possession, but rebounded by rolling up 71 total yards of offense – including an 18-yard touchdown run – in his first extended playing time of this preseason.
"We overcame adversity tonight," said Parker, who gained 31 yards on 10 carries with a touchdown and also caught three passes for 40 yards.
"I got into the end zone and I fumbled down at the end zone. I overcame adversity, but I'm not really satisfied with how I played."
With both teams playing their starters throughout most of the first half, the Steelers held a clear advantage, outgaining Philadelphia 297-89, with the defense recording three sacks. Despite having the ball with great field position throughout the first half, the Eagles managed only three points.
An interception on the Steelers' opening possession gave Philadelphia the ball at Pittsburgh 49. After driving to the Steelers' 23, back-to-back sacks knocked the Eagles out of field-goal range.
A 14-yard punt by rookie Daniel Sepulveda from his own end zone gave Philadelphia the ball at the Pittsburgh 20 on its second possession, but the Eagles were forced to settle for a 22-yard field goal by David Akers.
The Steelers drove from their own 26 to the Philadelphia 1 on their next possession, but Willie Parker fumbled on second-and-goal and the Eagles recovered to end the threat.
A muffed punt by Willie Reid pinned the Steelers back at their own 3 to start their next possession, and after a three-and-out by the Pittsburgh offense, the Eagles took over at the 44. Philadelphia, however, was again unable to generate any points.
"I like the way we smiled in the face of adversity," said Steelers head coach Mike Tomlin. "Really, we created some of that adversity ourselves. But I liked the way this team fights. They stayed together in a lot of tough situations. … Thankfully, the defense kept us in it."
That was it for Philadelphia quarterback Donovan McNabb, who finished 5-for 11 for 60 yards.
Working from their own 20, the Steelers finally broke through, going 80 yards in a drive capped by Parker's 18-yard touchdown run with 5:39 remaining in the first half for a 7-3 lead.
The Steelers added three points on their next possession, getting a 33-yard screen pass from Roethlisberger to Najeh Davenport with a personal-foul penalty tacked on at the end for a horse collar-tackle. It set up a 37-yard Jeff Reed field goal with less than two minutes left in the first half.
After forcing another three-and-out by the Eagles, the Steelers tacked on another Reed field goal, this one from 40 yards, with three seconds remaining in the half. Roethlisberger completed three passes on the drive, including a 25-yarder to Davenport, to get the team in scoring position.
The Eagles trimmed the lead to 13-6 with a field goal to open the second half – the fourth consecutive time this preseason an opponent has scored points on its opening possession of the third quarter.
But Charlie Batch, who replaced Roethlisberger to start the second half, continued his strong play, completing all three of his passes for 65 yards in a 79-yard drive that was capped by a 1-yard TD run by Kevan Barlow. That score put Pittsburgh ahead 20-6.
Rookie Kevin Kolb, Philadelphia's second-round draft pick, tossed a 4-yard TD pass to tight end Lee Vickers – who was in camp with the Steelers last season as a defensive end – with 4:14 remaining to cut Pittsburgh's lead to 20-13.
After the Eagles forced the Steelers to punt, Kolb drove Philadelphia to the Pittsburgh 28 at the two-minute warning. But rookie cornerback William Gay stripped tight end Zac Collie of the ball after a 6-yard gain and cornerback Jovon Johnson recovered, returning the ball 78 yards for a Pittsburgh touchdown.