EAST RUTHERFORD, N.J. (AP) -- While everyone may want to focus on the Dallas Cowboys not having the injured Tony Romo and Dez Bryant, they have lost four in a row because of their own mistakes.

There's plenty of fault to go around, and it was obvious Sunday in a 27-20 loss to the New York Giants.

-- Matt Cassel threw three interceptions in his first start for Dallas, including a pick-six by Dominique Rodgers-Cromartie.

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-- The Cowboys' special teams allowed former teammate Dwayne Harris to score on a 100-yard kickoff return with 7:01 to play, after Cassel had tied the game 13 seconds earlier with a touchdown pass to Devin Street.

-- Dallas (2-4) also lost four points after a penalty nullified Darren McFadden's touchdown and was forced to settle for a field goal.

-- Finally, any chance Dallas had to tie the game ended when Cole Beasley muffed a punt with 1:26 to play and the Giants (4-3) recovered.

"This is a tight group and we're not going to break. We give them credit. They made enough plays to win the game but we're going to keep battling and we'll learn from it," Cowboys tight end Jason Witten said. "We're still in the hunt. We're going to get it turned around and get it fixed."

There is a chance that Bryant will come back next week from the foot injury he sustained in the season opener against New York. Romo won't be back from his broken collarbone until mid-November.

"We haven't made a play when it was there all year," Dallas linebacker Sean Lee said. "We've had it in our hands and we've dropped them. You can't have big plays. For us, we have to have big plays, we have to finish plays and finish games. Last year, we did that well, but this year we haven't done that as consistently."

The win allowed New York to snap a five-game slide against Dallas and it gave coach Tom Coughlin his 100th regular-season triumph with the Giants.

Rodgers-Cromartie had two interceptions, returning one 58 yards for a touchdown. Brandon Meriweather also had a pick, while Myles White grabbed Beasley's muff to put it away.

Harris spent four seasons in Dallas without running back a kickoff for a score. But he tied a Giants record set in 1994 by romping untouched to the end zone.

"It felt great, especially my first return in the NFL, and it felt great coming against my old teammates," said Harris, who left Dallas because the Giants planned to use him as a receiver.

McFadden rushed for 152 yards and a touchdown, getting 29 carries after starting running back Joseph Randle left with a strained back.

Cassel forced some throws including the one Rodgers-Cromartie returned for his seventh touchdown in eight pro seasons, six by interceptions. He had a 57-yard run back with a fumble against Dallas in the season opener.

"I'm not going to make excuses," Cassel said. "I've got to do a better job. If you're throwing a comeback, you've got to see who you're going up against. Cromartie made two good plays today. You have to understand you're going up against a veteran corner. When you've been in the league as long as I have, you have to understand who you want to pick on and who you don't."

Two plays later, Cassel uncorked a wobbler down the left sideline for Terrance Williams, and Meriweather made a leaping pick at the Giants 1. Rueben Randle, making like receiving mate Odell Beckham Jr., followed with a terrific one-handed catch down the sideline on Brandon Carr, the same cornerback Beckham victimized last season for his play of the year. That 44-yarder immediately was followed by Shane Vereen's 39-yard burst, and Josh Brown completed the 83-yard drive with a 34-yard field goal for a 20-13 lead.

Cromartie's other interception, the third Giants pick within five throws by Cassel, led to nothing, and then Cassel found the range. He guided Dallas on an 80-yard drive, with a pinpoint pass to Street, whose first career TD came on a tip-toe reception.

Thirteen seconds later, Harris was sprinting down the right sideline for the winning points.

"You look at three interceptions, you look at the kickoff return, you look at the fumbled punt at the end of the ballgame," Cowboys coach Jason Garrett said. "Those things overshadow a lot of really good things we did. We had a lot of good things that happened in this ballgame. It's too difficult to overcome those kinds of mistakes in the National Football League."

NOTES: McFadden had a 1-yard TD and Dan Bailey made field goals of 30 and 48 yards for Dallas. ... McFadden last had a 100-yard rushing performance in Week 2 of 2013 while with Oakland.

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