OK, it helped that his defense scored a huge momentum touchdown at the end of the first half — and then hung on to withstand a final, furious threat at the end of the second half, surviving only when Dallas' 12th penalty of the game negated what appeared to be the winning score.
DeAngelo Hall returned a fumble 32 yards for Washington's only touchdown, and McNabb completed 15 of 32 passes for 171 yards in his Redskins debut Sunday night in a season-opening, when-do-we-exhale 13-7 win over the Cowboys.
The Cowboys (0-1) moved inside the Redskins 40 on three of their first four drives and didn't score a point, but the drive everyone will remember is the last one, which came after Graham Gano made a 49-yard field with 1:50 remaining to give the Redskins (1-0) a 13-7 lead.
After the kickoff, the Cowboys started at their own 19 with 1:45 left. They converted a fourth-and-10 at Washington's 43 when Tony Romo hit wide-open Miles Austin over the middle for a 30-yard gain with 12 seconds to go. Three plays later, Romo had only 3 seconds left on the clock, the ball at the 13-yard line. He scrambled to find Roy Williams open in the end zone.
But, while Williams and the Cowboys were celebrating, the official was calling Alex Barron for holding Redskins linebacker Brian Orakpo, negating the score and providing a fitting end to a game in which the Cowboys made mistake after mistake. Barron was starting because Marc Colombo missed the game with a knee injury.
McNabb was playing the Cowboys for the third straight game, the first player to do so since the 1970 merger. His Eagles lost to Dallas 24-0 to end the regular season in 2009, then 34-14 the following week in the playoffs in his last game with Philadelphia before the Easter Sunday trade that sent him to the Redskins. He now trails Romo 5-3 when the two quarterbacks go head-to-head.
Romo completed 31 of 41 passes 282 yards for the Cowboys. Austin caught 10 passes for 146 yards and scored the game's only offensive touchdown.
The Redskins opened a new era with McNabb and Shanahan and sported a retro look with burgundy jerseys and gold pants at home. LeBron James was among the 90,670 fans on hand for the prime time game, and even Albert Haynesworth got in the game for a dozen or so plays after a drama-filled offseason and training camp in which he was often at odds with his new coach.
A yawner of a first half was headed toward a plodding finish when Dallas coach Wade Phillips decided to try to score instead of run out the clock when the Cowboys got the ball at their own 30 with 27 records remaining. On the last play — with 4 seconds left when the ball was snapped — Romo threw short to Tashard Choice, who had the ball stripped by Hall with help from Lorenzo Alexander and Andre Carter. Hall picked up the ball and ran for the score, somersaulting into the end zone to give the Redskins a 10-0 lead into the locker room.
It was the first touchdown the Redskins had scored against the Cowboys since 2008, having settled for just two field goals in a pair of losses last year. The win also gave Washington a badly needed NFC East win, having gone 0-6 in the division during last year's 4-12 season under coach Jim Zorn.
The Redskins had a chance to pad the lead early in the second half. In fact, they did pad the lead when Gano made a 36-yard field goal, but Shanahan took the points off the board when Orlando Scandrick was called for offsides. With first-and-10 at the 13, the Redskins still couldn't punch it in, and their next field goal try went away when holder Josh Bidwell had the snap go through his hands.
Bidwell's miserable third quarter continued when he shanked a 27-yard punt on Washington's next possession, giving the Cowboys the ball at the Redskins 34. Romo needed only six plays to score, hitting Austin over the middle with a 4-yard pass with 1:41 remaining in the quarter.
The Redskins scored the game's first points by driving 69 yards for a field on a drive aided by a roughing the passer penalty on Jay Ratliff. McNabb scrambled for 17 yards to convert a third down, and a 14-yard gain on a screen to Chris Cooley led to Gano's 29-yard field goal.
Romo drove the Cowboys inside the Redskins' 40 on three of Dallas' first four possessions, relying heavily on screen passes, but two drives ended in punts and another proved fruitless when David Buehler's first NFL field goal attempt went wide right from 34 yards.