Giants wide receiver Mario Manningham makes a catch during training...

Giants wide receiver Mario Manningham makes a catch during training camp at the Quest Diagnostics Training Center in East Rutherford, N.J., on Monday, July 28, 2014. Credit: Brad Penner

The biggest obstacle to Mario Manningham's full-speed return to the field is not his knee but his mind. The wide receiver said he still is working up the courage to forget about the injuries that have derailed his last two seasons -- both with the 49ers -- and see what the surgically repaired joint actually can do.

"I know my knee is fixed, but it's just the confidence," Manningham said when asked what is holding him back. "It's me sticking my foot in the ground and going. Every day it gets better and better . . . I want to go out there and not think about it."

That may come soon. Manningham, who missed most of the spring, did not begin the season on PUP, which was a bit of a surprise. Slowly he has taken more and more reps in the offense, working toward the bottom of the depth chart. He said he knows that's where his journey to return to the Giants' roster really begins, even though he was a Super Bowl hero for the team just a little more than two years ago.

"What happened is in the past," he said. "This is still a new team to me. New faces. New staff. New offense. I'm going out there like I want to make this team, not like I already made the team or I got drafted here. I have something to prove also."

Manningham made the definitive catch of the Super Bowl XLVI victory for the Giants, then signed with the 49ers as a free agent. He never played a full season in San Francisco, undergoing a reconstruction in 2012 and then an arthroscopic procedure in January.

"I think he's still kind of getting his speed back and getting his feet back," Eli Manning said of Manningham. "You know he's a guy who can make plays for you. We have a good communication and just [need him to] be on the same page with me. He's still learning a new offense. He's only been out there a few days, so he's still learning on the run as well."

If he can stay healthy, Manningham will be a useful tool for the Giants' offense as a third or fourth receiver. If he can return to what he was before he left and was injured -- the player who caught 156 regular-season passes from Manning for 2,275 yards and 18 touchdowns over four seasons -- it will be a remarkable addition.

"I want to do the old stuff that I used to do," Manningham said. "Get some strength. My strength is getting there. Every day I feel better and better."

Manningham is trying to complete a comeback from two knee surgeries, but he’s also trying to complete a comeback with the Giants.

It is a rarity for players to return to a team for a second stint, but it’s certainly not unique. In recent years, a number of Giants have followed that path including Brandon Jacobs and Aaron Ross. All of them returned having experienced the world outside the New York Giants, and all of them raved about the little differences that the Giants provide that sometimes go unappreciated at the time.

Victor Cruz said that the players who have been career-long Giants hear those comments.

“One thousand percent,” he said.

Cruz signed a long-term deal last season, but he’ll likely have another contract in his NFL lifetime and may wind up playing elsewhere. But if he does, he’ll at least have listened to those who left and returned.

“Guys come back and they tell you the stories on how this place didn’t have that or it was just different than it is here, the love wasn’t the same, the type of people weren’t the same,” Cruz said. “Every organization is different and when they come back and they really love it and appreciate it, that goes to show you what type of organization this is and how grateful it is to be here.”

Manningham is the latest Giant to come back with that message.

“I think Mario enjoyed being a New York Giant,” Manning said. “Sometimes you leave and understand that you had a good thing going here. He left on great terms with the organization and had a great couple years here and went off and had some injuries in San Francisco but we’re glad to have him back and I think he’s glad to be back.”

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