What looked to be a significant injury Friday night turned out to be the case for rookie guard Marcus McKethan. He tore the anterior cruciate ligament in his right knee, was placed on the reserve/injured list on Saturday and will miss the entire 2022 season.

McKethan, a mammoth 6-foot-7, 335-pound offensive lineman, was primarily lining up at guard in training camp, but had been cross-training at tackle. He went down while pass blocking during the Blue-White scrimmage and had to be carted off the field at MetLife Stadium.

A fifth-round pick, McKethan was one of two offensive linemen from North Carolina the Giants selected in the draft. Another guard, Josh Ezeudu, was taken in the third round and currently is backing up Shane Lemieux at left guard.

This summer has not been kind to the Giants’ offensive line depth. Veteran Matt Gono, signed in the offseason to serve as the backup at left and right tackle, was placed on the exempt/left squad list Wednesday and is dealing with what could be a career-ending neck issue. That prompted the Giants to sign Will Holden, a 28-year-old swing tackle who has played in 27 games, with nine starts, for four different NFL teams.

Kayvon Thibodeaux has aced his first quizzes since coming to the Giants as the No. 5-overall pick in the 2022 draft. He looks the part and sounds the part, and in his first NFL training camp is consistently in the offensive backfield, shedding blockers and applying pressure to the quarterback.

His skills were on display during the Blue-White scrimmage. In his first action at the building in which he will play, with a crowd of about 26,000 on hand, the rookie from Oregon put constant pressure on Daniel Jones, actually had to be double-teamed on a few plays and drew two holding penalties, including one on left tackle Andrew Thomas.

“Well, he’s tough to block,’’ head coach Brian Daboll said. “He’s done a really great job these last few practices of getting his feet underneath him. He’s got a variety of pass rush moves. Again, he’s a rookie. We’ll see when the reps become live. He’s a good young player. He’s got a lot to work on.’’

Then, referring to the holding calls Thibodeaux induced, Daboll added, “I hope he draws more of ’em.’’

Jones, after a rough opening series, settled in and completed his night with a short scoring pass to Andre Miller, an undrafted rookie out of Maine. Jones’ first pass was nearly intercepted by Adoree’ Jackson for what would have been a pick-six.

“I thought he operated well,” Daboll said. “I’m sure there are plays he would’ve wanted back, but I thought he did a good job with his decision-making process. Made some good throws. But there’s certainly a lot to work on.”

Jones, on third-and-8 early in the evening, connected with rookie WR Wan’Dale Robinson for a 28-yard pickup, but the pass likely would not have been launched in a real game, as no contact with the quarterback is allowed in practice. CB Darnay Holmes came free, ran at Jones and then peeled off to avoid contact.

Here is how to get noticed in a positive way: CB Darren Evans deflected a pass into the end zone thrown by Davis Webb, and safety Yusuf Corker came away with the interception he took back a long way. Another notable sequence: Tyrod Taylor hit WR Austin Proehl for what should have been a touchdown, but CB Michael Jacquet knocked the ball away from Proehl at the 1-yard line and safety Jarrod Wilson, signed earlier in the week, recovered the fumble.