Aikman Is Injured as Cowboys Win : NFC: After impressive showing, Dallas quarterback leaves in third quarter of 31-9 victory over Giants with hamstring strain.

Troy Aikman got the Dallas Cowboys back into first place the hard way.

Aikman put on an impressive display that included 10 consecutive completions and two touchdown passes to Alvin Harper before leaving with a slight hamstring strain in a 31-9 victory over the New York Giants Sunday.

“We don’t know how serious the injury is, but at first look it appears Troy will be out only a short period of time,” Dallas Coach Jimmy Johnson said. “We did a good job of taking up the slack when Troy left. The defense did a good job.”

The defending Super Bowl champions earned their sixth consecutive victory after starting the season 0-2 without Emmitt Smith. The Giants dropped to 5-3 and fell a game behind the Cowboys in the NFC East.

Aikman went down while being chased by defensive end Keith Hamilton with 9:30 remaining in the third quarter and Dallas leading, 17-6. Aikman’s left shoe stuck to the artificial turf and he collapsed with a grimace.

Robert Vandermeer, team physician, diagnosed the problem as a strained left hamstring. “It will be re-evaluated (today),” he said. “We hope it’s not too bad. We’re treating it with ice.”

Dallas trainer Kevin O’Neill said: “There’s no tear. We want to see how he responds in 24 to 48 hours. It will tell us more. But I wouldn’t rule out the possibility he will play next week against Phoenix.”

Said Aikman: “I could feel it when it pulled. It was frustrating. You don’t like leaving the field when things were going like they were.”

Aikman returned to the sidelines in street clothes with the hamstring wrapped in ice as Jason Garrett took over as quarterback. Garrett completed five of six passes for 34 yards.

Smith scored on runs of one and two yards in the fourth quarter to cap two 51-yard drives that put the game away. The second touchdown was set up by a surprise 46-yard pass play from Harper to Irvin.

Smith, who suffered a bruised shoulder, rushed 24 times for 117 yards and left with the game well in hand late in the fourth quarter.

“We were very concerned going into the game and it felt good to win and get back into first place,” Smith said.

Said Johnson: “The biggest thing we have to worry about is to start thinking we are pretty good. I think we did a good jog against a pretty good football team.”

Aikman completed 11 of 13 passes for 161 yards. He took advantage of single coverage on Harper to throw 28- and 50-yard touchdown passes in the first half, which ended with Dallas ahead 17-6.

The Dallas defense had five sacks and dominated the Giants after a shaky start.

The Giants bungled two chances for touchdowns and had to settle for field goals of 21 and 45 yards by David Treadwell in the first half.

A holding call on guard Bob Kratch negated a seven-yard touchdown pass from Phil Simms to Mark Jackson, and a 47-yard Simms-to-Chris Galloway pass to the Dallas 25 positioned the Giants for a touchdown, but a flea flicker backfired. Lewis Tillman tried to lateral back to Simms but tossed the ball wildly to the Cowboys’ 44. New York couldn’t move and settled for a second field goal.

“There’s no question who has the better team,” said New York Coach Dan Reeves. “They beat us in all three phases. This was a good measuring stick and it shows we have a long way to go to be as good as they are.”

Simms completed 12 of 21 passes for 155 yards. Backup Kent Graham completed six of 15 passes for 59 yards. Tillman ran 19 times for 82 yards.

“We had our chances but mistakes killed us,” Simms said. “If we could have scored touchdowns on our two chances in the first half the game might have been different.”