EAST RUTHERFORD, N.J. — Christian Hackenberg jogged onto the field at MetLife Stadium to cheers from New York Jets fans who had been waiting all summer to see the rookie quarterback play.

He gave them a lot more to be excited about just a few minutes later.

The second-round draft pick from Penn State threw a touchdown pass on his first drive in an up-and-down NFL debut in the Jets’ 21-20 loss to the Giants on Saturday night. He also tossed an interception in Jets territory that set up the Giants’ go-ahead score.

“He made some throws, but he missed some throws,” coach Todd Bowles said. “It was good to get his feet wet.”

After Hackenberg replaced Bryce Petty early in the fourth quarter, he got off to an inauspicious start with two incomplete passes and a delay-of-game penalty.

Then, he got rolling.

Hackenberg hit Zach Sudfeld for 16 yards on third-and-15, then connected with rookie Charone Peake for 26. After Antone Smith’s 1-yard run, Hackenberg threw a 27-yard pass to rookie Robby Anderson.

On the next play, Hackenberg lofted a perfectly placed toss into the right corner of the end zone to Anderson, capping an impressive first drive.

“It was sweet,” Hackenberg said after the game. “I wanted to go celebrate with my guys. I thought it was big for us and the team at that point in time. “