The only way for Daniel Jones to mount a serious challenge this summer to overtake Eli Manning for the Giants’ starting quarterback job is for him to arrive at his first NFL training camp and put on a show. Before he can do that, he must sign his contract. Jones is one of five first-round picks around the league yet to come to terms.

There is no cause for alarm, even though the clock is ticking. Jones is scheduled to report Monday, when all rookies and select veterans report to camp. Two days later, the entire roster arrives and the first practice is set for July 25.

Jones is expected to be there on Monday with all the other rookies. At that time (or prior to that), he is expected to sign a four-year deal that will pay him $25.5 million, with $16.6 million in guaranteed money. That is the financial slot Jones occupies as the No. 6 overall pick in the draft, a slot that almost never gets altered when it comes to dollars and cents. What most likely is holding up the agreement is language in the contract — language that figures to get cleared up in time for Jones to hit the field along with his new teammates.

A year ago, running back Saquon Barkley arrived as the Giants’ No. 2 pick in the 2018 NFL Draft and signed his four-year, fully guaranteed $31.2 million deal the day he reported.

Another Giants player, outside linebacker Oshane Ximines, also is one of the nine unsigned players from the late-April draft. Ximines, a third-round pick (95th overall) from Old Dominion, is a pass-rush prospect. He will receive a four-year deal worth $3.3 million, with around $880,000 in guaranteed money.

Other than Jones, the unsigned first-round picks are No. 2 Nick Bosa (49ers), No. 3 Quinnen Williams (Jets), No. 5 Devin White (Buccaneers) and No. 16 Brian Burns (Panthers).

“I think for everyone, training camp is the next opportunity to improve as a player,’’ Jones said last month. “I am looking forward to that and to getting back and taking those steps. I think everything will be ramped up a little bit in training camp. I think that’ll be the next step in the process and the next step to improve.’’

Coach Pat Shurmur, following the Giants’ offseason program, stressed Manning is the starter, but did not dismiss Jones as a backup with no chance to supplant the veteran.

It was no secret the Giants had keen interest in Jones, but his selection by general manager Dave Gettleman so high in the draft was widely criticized as a reach. Jones, a Manning look-alike from Duke, was impressive in the spring, showing athleticism and a stronger arm than advertised.

“I think I have certainly made progress and am a lot closer than I was the first week of [organized team activities],’’ Jones said. “I think that is positive. As far as am I ready … I am not sure. I have never played. I am improving and making progress.’’