The juxtaposition was jarring, even as Giants coach Pat Shurmur insisted Friday that “nothing has changed’’ regarding the pecking order at quarterback, which remains Eli Manning as the starter and Daniel Jones as the backup.

The preseason opener showed a brief glimpse of Manning and a slightly more extended view of Jones, surely not enough to warrant any sea change on the depth chart. Yet the one pass Manning attempted in his three snaps on the field and the five passes Jones competed in his eight snaps show a contrast that might mean little now, but could gain relevance later.

Jones went 5-for-5 in Thursday night’s 31-22 victory over the Jets and distributed the ball to almost all corners of the turf. He kept his eyes up and his sightlines clear on a toss to the left that turned into a 31-yard completion to Cody Latimer. He impressed his teammates immensely on a gutsy throw into the end zone for a 12-yard scoring strike to Bennie Fowler.

There was no hesitation at all from Jones.

Shurmur gave Manning one series and hoped it would last longer. The first play, a bootleg, resulted in a short flip to tight end Scott Simonson, who was dropped by linebacker Brandon Copeland for a three-yard gain. Two Wayne Gallman runs produced only one yard, and the Giants punted the ball away.

Did Manning get all he could have out of his time on the field? Fans who once adored Manning have grown weary of check-downs. Rather than settle for a modest gain to Simonson, Manning might have been able to hit his other tight end, Rhett Ellison, beyond the first-down marker.

“Certainly quarterbacks are always trying to keep their eyes downfield,’’ Shurmur said. “So we got a completion. You could make the case he could have thrown the ball down the field to Rhett. But you move the chains and you move on.’’

The Giants did not move the chains on that series, and Manning took his place on the sideline.

“He’s our starter, and I think it’s important he played to some degree,’’ Shurmur said. “The idea was not to go three-and-out. The idea was to go on a scoring drive.’’

When the Giants return to practice on Sunday, Manning will continue to work with the starting offense, a role Shurmur continues to stress, but not guarantee, Manning will fill Sept. 8 in the regular-season opener against the Cowboys.

“Listen, we’re not going to play the what-ifs,’’ Shurmur said. “I would say this: Nothing has changed. This was the first game. I expect Daniel to play well. I expect him to go out and improve, and for the people that don’t know him, impress them. Our expectations for him have not changed. In my mind, that situation has not changed.’’

There is an appetite for exposing Jones to as much as possible — Shurmur is especially interested in having Jones run a two-minute drill this summer. As polished as the Giants believe Jones to be, he is still an NFL novice, while Manning has an advanced degree.

On Jones’ very first snap, he greatly benefited from having someone by his side capable of spotting a mistake and making the necessary correction. That someone was Gallman, the third-year running back who started in place of Saquon Barkley.

“He could have gotten killed,’’ Gallman said, referring to Jones. “I had to save him.’’

Jones took the field and immediately blew the protection call. Ellison was positioned on the right side of the line, and Jones failed to alert Ellison to come in motion to help fortify the left side.

Left tackle Nate Solder blocked inside on Quinnen Williams, leaving outside linebacker Jordan Jenkins with what for an instant was a clear lane to Jones. Gallman recognized something was amiss and slid over, quickly, to put a block on the 259-pound Jenkins, impeding his progress enough to allow Jones to complete a five-yard pass to Latimer.

Mental errors might go unseen outside the circle, but inside it, they are the reason there is a reluctance to put most rookie quarterbacks on the field before they are primed to make the proper calls.

“In my mind, that’s the game within the game,’’ Shurmur said. “There’s a lot of things that happen behind the scenes that we certainly take into account all the time with all the players.’’

The experience factor means Manning starts. How quickly Jones can narrow the gap will determine what comes next.