At least the Dallas Cowboys are consistent. They've enjoyed coming from behind to win games so much this season that they can't get out of the habit, no matter how hard they try.

Today, they found themselves trailing the lowly Philadelphia Eagles going into the fourth period before a blocked punt by a second string tight end helped them salvage a 16-10 victory.

Until Jay Saldi broke in on Eagle punter Spiro Jones and blocked the kick, which was picked up by Charlie Waters and returned 17 yards for a touchdown, the Cowboys were finding every way possible to lose their first game.

They were dropping passes, missing extra points and field goals and messing up their line blocking enough to keep the Eagles ahead, 7-6.

Had the Eagles been able to generate any kind of offense against the rugged Dallas defense, the Cowboys would have had a much sadder flight home.

Eagle quarterback Ron Jaworski suffered a fractured thumb on his passing hand and a mild concussion when he was sacked by former Maryland star Randy White in the second quarter. Jaworski was out of the game briefly, but came back to finish up.

He completed 10 of 23 passes for 104 yards, was sacked four times and intercepted twice.

He said he would undergo special treatment and hoped to be ready for the Redskin game next week.

The more Jaworski struggled the longer Dallas had to get the big play it needed to turn the game around. That opportunity finally came with 14 minutes left in the contest.

With fourth and nine, Jones dropped back to punt on his 33. Dallas twice had put a rush on him, and each time Waters had just missed blocking the ball.

This time, the Eagles blocked Waters coming in from the side, but left Soldi who was coming up the middle, untouched. "They had been blocking me all game," he said. "But this time I was really surprised. I had a free lane to the kicker."

Saldi hit the ball cleanly and it bounded toward the right sideline. Waters raced over, picked it up and charged into the end zone for the score.

Efren Horrera, who had missed two field goals and had an extra point blocked, failed again on the conversion. But the Eagles had too many men on the field and his second try was true for a 13-7 Dallas lead.

He later booted an 18-yard field goal that was set up by a 33-yard run by quarterback Roger Staubach on a broken play. It was the longest run of Staubach's nine-year career.

"That's how we played today," said Cowboy coach Tom Landry. "Our biggest gainer comes on a busted play.Our backs didn't hear the audible and Roger was left on his own. So he pulls off a great bootleg.

"As long as we win, I like it, even if we keep coming back in the second half.We did it the last two weeks agains St. Louis and Washington and these people keep finding ways to do it again."

Those victories over the Redskins and Cardinals left Dallas flat for this one, something Landry readily admitted afterward. But a fine effort by the Eagle defense, which confused Staubach at times with its varied secondary coverages, had a lot to do with the Cowboy's inconsistency.

Dallas probably could have put the game away early, but couldn't get any points in the first period despite two long drives into Eagle territory.

Instead, it was Philadelphia that struck first, marching 56 yards on 15 plays to score on a 12-yard pass from Jaworski to Charlie Smith, who had beaten Mel Rentro in the corner of the end zone. Jaworski earlier had completed two long third-down passes to keep the threat alive.

Dallas finally got on the board with 1:10 left in the half on a five-yard run by Tony Dorsett, who played sparingly and gained just 48 yards on 13 carries. Dorsett set up the score with a fine 12-yard burst up the middle one play earlier. But Art Thomas blocked Herrera's conversion attempt to keep the Eagles ahead.

On the next series, White hit Jaworski from the blind side. "I know he never saw me," said the Dallas defensive tackle - and Jaworski fumbled. The Cowboys recovered on the Eagle 25 but a 34-yard Herrera field-goal attempt was wide. The game then became a standoff until the blocked pant.

Staubach completed 14 of 25 passes for 170 yards, but his receivers treated him unkindly, dropping at least five catchable passes, including one by Preston Pearson on the goal line in the first quarter.