Foxborough, Mass. - The New England Patriots lost for the first time in 11 home openers at Gillette Stadium. They may have also lost one of their most dynamic and dangerous offensive weapons for a while.

Tight end Aaron Hernandez injured his right ankle midway through the first quarter of New England's 20-18 loss to the Arizona Cardinals on Sunday and did not return.

He left the stadium after the game wearing a walking boot.

"Hopefully, he's fine," said fellow tight end Rob Gronkowski, who caught a 5-yard touchdown pass from Tom Brady with 2:06 remaining before the Patriots failed on the 2-point conversion pass to Gronkowski that would have tied the game. "He's a great player and we need him."

After a sluggish start, New England (1-1) made it 20-12 on Stephen Gostkowski's fourth field goal of the game, a 53-yarder, with 6:45 to play. Following a punt by Arizona (2-0), Brady capped an 11-play, 82-yard drive with the touchdown pass to Gronkowski.

The Patriots got the ball back with 1:01 to play, though, after Arizona running back Ryan Williams fumbled and Vince Wilfork recovered. But Gronkowski stalled any momentum New England may have mounted when he was whistled for holding, a call that nullified a 30-yard run into the end zone by Danny Woodhead, and a false start two plays later.

"It felt like it was a clean block, like my hands were inside," Gronkowski said of the holding call. "The penalty (flag) was thrown, you guys saw it too. You probably saw the replay, so you can tell me if my hands were outside or not."

Instead of trying to move closer, New England was content to try and win the game on a 42-yard field goal with 6 seconds left, but Gostkowski missed it wide left.

"You get opportunities like that not very often and I have to do a lot better job of coming through for the team," said Gostowski, who had been 3 for 3 in his career on field goals that would have tied or won the game in the final two minutes. "I had a chance to win it and it came down to me and I didn't pull through and it stinks."

The loss snapped a five-game winning streak against Arizona and was New England's first in a home opener since Gillette Stadium opened in 2002.

On the Patriots' third offensive play of the game, wide receiver Julian Edelman caught a short screen pass from Brady and followed Hernandez's block up the left side before landing awkwardly on the tight end's right leg.

Hernandez, who recently signed a long-term contract extension, was writhing in pain on the field for a few minutes before being helped to the locker room.

With Hernandez sidelined, New England's wasn't its usual explosive self. Brady was just 14 of 25 for 150 yards through three quarters before leading a fourth-quarter charge.

"Aaron is in there almost every play, so it changes quite a bit," Patriots receiver Wes Welker said of their game plan. "You have to go to a different attack and go out there and play the way we need to and execute the way we need to and today just wasn't enough."

The game was tied at 6 at halftime on two field goals each by Gostkowski and Jay Feely.

The Patriots took their only lead on Gostkowski's 51-yarder 2 minutes into the third quarter. But the Cardinals responded with consecutive touchdowns to go ahead 20-9 on Kevin Kolb's 2-yard pass to Andre Roberts, after they got the ball at the 2-yard line on a blocked punt, and a 5-yard run by Kolb.

"Nobody really gave us a chance," said Arizona coach Ken Whisenhunt, whose team was a two-touchdown underdog, "but our guys believed they could do it and it's great to see them operate that way."

Kolb filled in for John Skelton, who sat out with a sprained right ankle, and completed 15 of 27 passes for 140 yards.

Brady was 28 for 46 for 316 yards and extended his streak to 34 games with at least one touchdown pass, fourth-best in NFL history. But the Patriots didn't try to move the ball into better position for the final field goal attempt.

"It's just a decision that Coach (Bill Belichick) makes," Brady said. "We shouldn't have been leaving it up to that particular situation."