CLEVELAND — First play: Fumble on the kickoff.

First play from scrimmage: Deshaun Watson to Amari Cooper for a 24-yard touchdown connection.

Eleven seconds into the game and the Giants were down by a touchdown.

Brian Daboll was looking up to the heavens.

It was the third anniversary of the death of his grandmother, the woman who raised him growing up.

“I was kind of giving her the business after the first two plays,’’ Daboll said. “Like ‘What do you have in store for me?’ ’’

There was plenty in store for Daboll and the Giants on a Sunday afternoon filled with lows and highs, exhilaration and tension, more exploits from rookie sensation Malik Nabers, chances to put things away, then chances to blow it.

In the end, there was a first for the Giants with their 21-15 victory over the Browns at Huntington Field.

“It feels good to get out on the board, get off that donut,’’ defensive end Brian Burns said.

The donut — a zero in the win column — is no more, as the Giants tried every which way to do what seemed impossible — turn a rousing and rare triumph into a devastating defeat.

The Giants after building a comfortable lead got all sorts of uncomfortable. A 21-7 lead was trimmed and threatened but it never went away.

“Showed a lot of resiliency on the road,’’ Daboll said.

After an 0-2 start, the Giants could not absorb another loss.

They swarmed and made Browns quarterback Deshaun Watson look dreadful, sacking him eight times.

After the instant deficit — it was Eric Gray who lost the fumble on the opening kickoff — Daniel Jones and Nabers got cooking and the Giants actually looked as if they might make things easy on themselves.

The offense took a nosedive in the second half, though, coming up with no points and allowing the Browns (1-2) to make a game of it.

Jones finished 24 of 34 for 236 yards. Nabers had eight catches for 78 yards. The duo combined for two touchdown hookups 93 seconds apart in the second quarter.

Down 7-0, Daboll in the first quarter rolled the dice by going for it on 4th-and-1 on his own 43-yard line (Nabers ran for two yards on a jet sweep to pick up the first down).

That kept alive an 81-yard drive capped by Devin Singletary ramming it in from a yard out to make it 7-7.

That was the start of the most impressive stretch of play from the Giants this season.

Jones, who completed 20 of his first 22 passes, looked like a point guard, directing the ball where it needed to go as Daboll kept things moving with all sorts of screens and short stuff to thwart the Browns defensive aggression.

Nabers made the biggest splash by taking the ball away from cornerback Martin Emerson on what could have been an interception and ended up as a 28-yard reception — a classic 50-50 ball that Jones entrusted the rookie to get.

“DJ told me if he throws it up there it’s me or nobody,’’ Nabers said. “I tried my best to put my hands in front of his hands, did a great job of snatching it away.’’

Nabers finished what he started by losing Emerson and then coming up with a leaping grab in the left corner of the end zone to make it 14-7 with 1:44 remaining in the first half.

“I have a lot of trust in him going up and getting the ball,’’ Jones said.

The Giants got the ball back when Burns made his first impact play for his new team, abusing right tackle Dawand Jones for a strip-sack of Watson, with Elijah Chatman pouncing on the ball on the Browns 30 with 32 seconds left before halftime. Jones found Nabers in the back of the end zone, there was another leap and the Giants soared in at the break, ahead 21-7.

Singletary lost a fumble to ruin the first series of the third quarter and the offense dried up. Watson hit Cooper for a 6-yard scoring pass to make it 21-13 with 11:33 remaining. The Browns went for two and got it when Watson found Jerry Jeudy.

Three times, the Giants needed to make a stand on defense. They got a break when Jerome Ford fumbled and Azeez Ojulari recovered with 7:40 to go. The Giants offense, still stymied, could not take advantage and had to punt the ball away with 5:19 to go.

Next, Kayvon Thibodeaux and Jason Pinnock stopped Jameis Winston’s quarterback sneak on third-and-1 and Dexter Lawence’s leg-tackle on Watson dropped him short of the first down with 3:36 left.

The Giants had a chance to put the game away but newly signed kicker Greg Joseph missed wide right on a 48-yard field goal try with three minutes to go.

Time for another last stand. Banks was closest to Cedric Tillman — Cooper was off the field with an injury — on a key fourth down and Tillman could not hold onto the ball with 2:33 left to seal the deal for the Giants as they head into a short week before facing the Cowboys on Thursday night.

“It feels like a relief,’’ Nabers said. “We get to go rolling into the game next week with that win on our backs instead of going into the next week with a loss. It’s way better.’’