The Giants were able to exhale Monday when they learned rookie cornerback DeAndre Baker did not sustain a serious injury to his left knee and might not miss substantial time.

Baker was diagnosed with a sprained knee. The diagnosis was confirmed Monday morning by team physician Scott Rodeo after he examined Baker and checked out the results of an MRI exam at the Hospital for Special Surgery.

The Giants say Baker is day-to-day.

“Yeah, it’s a big relief, certainly,’’ coach Pat Shurmur said. “He’s been coming along real well and I think to know it’s not serious at this point is good.’’

Baker sustained the injury while warming up on Sunday. He watched the second half of Monday’s practice from the side and was not wearing a brace on his knee.

“That’s a blessing,’’ second-year cornerback Grant Haley told The Post. “He was a little down yesterday so hearing that news was probably good for him. He’s had great OTAs and up to camp now, he’s kinda getting in a groove, watching the game you could see why he was drafted so high. When someone goes down like that and he’s starting to have that confidence you can only help them pick that confidence back up and remind him how well he was doing when he was healthy.’’

The Giants traded up to take Baker with the 30th pick in the NFL draft. He is a starter on defense.

The Giants continue to await word of WR Golden Tate’s appeal of his four-game suspension for violating the league’s Policy on Performance Enhancing substances.

“Again, we’re waiting just like the rest of the world is,’’ Shurmur said. “I don’t know. Originally it was reported that it was three days. It’s not three days, obviously. I think it can take as long as it needs to.’’

Shurmur had a large scratch on the left side of his face.

“I was putting the dog out,’’ he said. “She’s a big girl, and she kind of ran between my legs and I just fell.’’

It sounds as if Eli Manning will play in the second preseason game, Friday night against the Bears. Shurmur said he would like to get all four quarterbacks in the game, if possible.

The three-and-out series to start the preseason opening victory over the Jets came after Manning handed off to Wayne Gallman on a third-and-8 draw play — certainly a low-percentage call hoping to pick up a first down. Shurmur said it was a draw-pass check and that Manning noticed both safeties were deep.

“We had a favorable look to run the ball, and it didn’t work out,’’ Shurmur said. “So, if you’re second-guessing, then go ahead.’’