Philip Rivers leads the Chargers to their first win after a messy first half

Philip Rivers’ messy fingerprints were all over the first 40 minutes of Sunday’s game in MetLife Stadium, a brutal stretch of football that the Chargers somehow overcame to notch their first win of the season, a 27-22 victory over the New York Giants.

There was a miscommunication on a snap that led to the Giants’ first-quarter safety, when Spencer Pulley’s shotgun snap to an unsuspecting Rivers bounced off the quarterback and into the end zone. Rivers batted the ball out of the back of the end zone so a defender couldn’t fall on it for a touchdown.

Just before halftime from the Giants 29-yard line, Rivers put far too much on a pass to Travis Benjamin, who was so wide open in the end zone that no defender was in the picture when the play was aired on stadium video boards. The ball went off Benjamin’s fingertips, and the Chargers settled for a field goal.

Then, with the Chargers on the cusp of extending a one-point lead early in the third quarter, Rivers’ poorly thrown pass intended for Keenan Allen in the end zone was intercepted by New York free safety Darian Thompson.

The Giants converted the turnover into a go-ahead touchdown — driving 80 yards in nine plays — with Eli Manning hitting Roger Lewis Jr. for a 29-yard score and a 16-10 lead with 6 minutes 46 seconds left in the third quarter.

“I was as fired up and aggravated as I’ve been this year on the sideline,” said Rivers, who completed nine of 22 attempts for 89 yards in the first half, skidding some throws onto the turf and sailing others over their intended targets.

“It’s funny because the guys that know me, they’re thinking, ‘Here he goes, this is how he gets himself going, and he’s trying to get us going.’ The guys who don’t know me are probably thinking, ‘What in the world is going on? Is he about ready to hang it up for the day?’ It’s tough, but I have to fight through that.”

Rivers carried on the only way he knows how. He came out firing, furthering his reputation as a gunslinger, driving the Chargers 92 yards on 12 plays for a touchdown that gave them a 17-16 lead with 40 seconds left in the third.

New York went ahead again 22-17 on Manning’s 48-yard touchdown pass to Odell Beckham Jr. early in the fourth, but Nick Novak’s 31-yard field goal with 4:50 left pulled the Chargers within 22-20.

Defensive end Melvin Ingram’s huge sack of Manning and ensuing fumble recovery gave the Chargers the ball back at the Giants’ 11 with 3:46 left, and Rivers tossed a 10-yard touchdown pass to Melvin Gordon for the winning score.

“Kobe Bryant said it best,” said Allen, who caught four passes for 67 yards. “You miss a lot of shots, what do you do? You keep shooting. You miss some throws, you keep throwing.”

Rivers finished with 258 yards passing, completing 21 of 44 attempts, to pass Fran Tarkenton for 10^th place on the NFL’s all-time career passing list with 47,198 yards.

He certainly wasn’t perfect but was spot-on when he needed to be on a key third-quarter drive. On a third-and-nine from his nine-yard line, Rivers completed a 12-yard pass to Antonio Gates, who went to his knees for the first-down catch.

On a third-and-15 from the 16-yard line, Rivers threaded a pass between two defenders to Allen for 16 yards. Two plays later, he teamed with Gordon on a 22-yard pass play. On third-and-six from the Giants 43, Rivers hit Allen, who made a leaping catch over the middle for 18 yards.

The touchdown was a 25-yard strike to tight end Hunter Henry, who made a lunging catch in the back corner of the end zone.

“You throw an interception, you have to bounce back — it’s part of playing quarterback in this league,” said Rivers, who has been picked off five times this season. “I was sick about [Sunday’s interception] because I felt like we were gaining some momentum, we gave it right back to them, and they went down and scored.”

Neither Rivers nor the Chargers defense let that interception define them Sunday. Unable to execute at the right time or make the big plays at the end of their first four games, the Chargers bounced back from their early struggles and cashed in on an opposing team’s mistake at the end.

“At halftime, I thought, ‘Ooh, we can’t get worse than that,’ ” Allen said. “That’s the NFL, man, you have to be able to wash it off. You have to have a short-term memory. You have to play four quarters, not two quarters, not 1 1/2 quarters, not a half … it’s 60 minutes.”

mike.digiovanna@latimes.com

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