Wayne Gallman saw it often enough at Clemson that he is not at all surprised that his former college quarterback, Deshaun Watson, is lighting things up for the Texans.

“That’s what he does,’’ Gallman said Wednesday after practice. “When you play at something that you love, you have fun with it, and it shouldn’t be anything else other than that. It shouldn’t be hard going out here playing, it should be fun. That’s what we had at Clemson, and that’s what we bring in the NFL.’’

No one is saying Gallman has made anything close to the impact fellow rookie Watson has imprinted on his team in Houston, but at this point, four games into a winless season, the Giants will take anything they can get as far as glimpses of anything positive.

In his NFL debut, at Tampa Bay, Gallman was a bright spot amid the darkness — rushing 11 times for 42 yards, catching a 4-yard touchdown pass and actually making the Giants rushing attack look adequate.

“Wayne’s a young player who plays fast,’’ coach Ben McAdoo said. “I think you saw the speed when he jumped onto the field. He has electricity in his game. He’s a talented, young player. He has a lot to learn, but he’s very, very willing and works hard at it.’’

Words like “speed’’ and “electricity’’ are not often linked to the stable of running backs assembled by the Giants. Gallman helped the Giants rise from 32nd to 30th in the NFL in rushing, averaging 59.3 yards per game and 3.2 yards per rushing attempt. Paul Perkins (ribs) and Orleans Darkwa (back) were limited in practice, but no matter who is healthy and who is hobbled, Gallman should be included in the offensive game plan and given the ball Sunday against the Chargers in a meeting of winless teams.

“I was impressed with myself,’’ Gallman said. “Just watching NFL football and how it is, I guess it was a lot. I felt like there was more out there. I played really only one half. Best is yet to come.’’

Gallman was inactive the first three games and played 31 of the 80 offensive snaps against the Buccaneers. The wait, he said, was not excruciating, as he used the time to prepare for his first opportunity.

“Well, actually at Clemson we were a pass-based offense, so carries were limited, every carry meant something, had to put your max output into every carry,’’ he said. “I know how it is. I’m used to it. Whether it’s five or 20, I’ll be willing to do everything I have [to].’’

There is more to earning the trust of the coaching staff than what Gallman does with the ball in his hands. He needs to show he can pass-protect, something he did expertly when he took on 281-pound defensive end William Gholston, stopping the bigger defender in his tracks to provide Eli Manning the time he needed to complete a pass.

“I just had to hit him … big dude, man, can’t let him hit Eli,’’ Gallman said.

“He’s grown there,’’ McAdoo said. “He still has some work to do. He’s come a long way as a striker as well. Learning how to strike for a young back, that takes a little time. But again, he’s a hard worker and he’s willing.’’

Gallman’s debut came on his 23rd birthday, and he said he did not celebrate much, declaring he tries to “be a homebody.’’ His girlfriend, Lexi Carter, is the starting point guard on Clemson’s women’s basketball team and the pull of the big city has not drawn him in.

“I try to stay indoors,’’ Gallman said. “I go out to the movies, I go out to eat, if not with my girlfriend I go by myself. I’m very laid back.’’

Told that running backs are flashy, as opposed to laid back, Gallman said, “I didn’t say I wasn’t flashy, I just like to chill. If guys want to step out, I’ll step out, but I’m not gonna be the first to do that. You step out, bad things can happen, so why don’t you just stay home and chill?”

McAdoo said, against the Buccaneers, Gallman showed “it wasn’t too big for him.’’ Gallman previously had expressed confidence he was ready, and then delivered.

“I knew I could help,’’ he said. “I feel I did what I was supposed to do. I know what I can do so it’s pretty natural.’’