Baylor Scheierman didn’t lace up on Sunday night. He still made an impact.

The 24-year-old Celtics wing led on and off the floor for the Celtics in an undeniable way.

LAS VEGAS — In the Celtics’ Summer League finale, Baylor Scheierman sat in street clothes at the end of the bench. He was officially done with on-court action after four games, and this time, he and fellow Summer League vet Jordan Walsh were both getting the night off.

But Scheierman could barely sit.

The 24-year-old Celtics forward was on his feet nearly every possession, cheering the other guys after every hustle play or well-executed defensive possession.

Scheierman’s cheers were particularly loud for Aaron Scott, one of 7 players on the Summer League roster who aren’t currently slated to be a part of the Celtics organization next season. Scott, who averaged 8.4 points, 4.3 rebounds, and 1.4 steals at St. John’s last year, had yet to make his Summer League debut when the finale — a consolation game against the Atlanta Hawks on Sunday afternoon — came around.

So, when Scott heard this name called midway through the first quarter, he sprinted into the court, suppressing a grin.

And, Scheierman immediately rose to his feet.

“Let’s go, Aaron!” Scheierman belted after Scott first checked into the game.

“Yeah, Aaron!” he yelled when the undrafted rookie grabbed four rebounds in his first three minutes on the floor.

Scheierman and Scott didn’t know each other well before Summer League began. The two both played in the Big East — Scheierman for Creighton and Scott for St. John’s — but hadn’t crossed paths much before this summer.

But, Scott said that the Celtics’ returner took him under his wing when training camp started, and that throughout Vegas, Scheierman emerged as a mentor.

“I’ve been a sponge with Baylor,” Scott said. “He’s been at this level for a couple of years now, and I’ve been listening and learning from him.”

Celtics rookie Amari Williams also credited Scheierman (and Jordan Walsh) for leading the group.

“Any time any of the rookies or new guys were confused, that’s who we’d look to,” Williams said in his postgame interview on the ESPN broadcast.

In the season finale, Scott’s impact was undeniable. He ultimately tallied 9 rebounds (7 offensive), 3 assists, a steal, and a block in 18 minutes off the bench. He missed his first three three-pointers, but sank the fourth, inciting raucous cheers from Scheierman and the bench. The Celtics walked away with a 100-81 victory.

“That’s exactly the type of player he is,” Summer League head coach Matt Reynolds said of Scott’s rebounding. “It’s not the easiest thing to do — to sit for essentially four games, come in and just be a relentless crasher.”

Where does Aaron Scott go from here?

The 6’6 wing is looking to carve out a 3&D role in the NBA: “I just got to knock down my threes, but the defense is there,” he said, noting he’s always been a player who makes extra hustle plays.

Scott could find a spot on a G League team, or ultimately go overseas, as many Summer League players have done. (Last season, Kenny Lofton played in China and Isaiah Wong played in Lithuania, among others.)

Sources told CelticsBlog that at least one player from the Celtics’ Summer League roster — guard Hayden Gray — has signed with the Maine Celtics, Boston’s G League affiliate. Where Scott and the other non-rostered players go next has yet to be determined.

But, Reynolds and the coaching staff will continue supporting the 14 guys on the Summer League roster regardless of where they go next.

“I told them, I’ll be forever rooting for that entire group,” Reynolds said after the game.

Photo by Candice Ward/Getty Images

Baylor Scheierman impacted winning despite shooting struggles

It’s no secret that Scheierman struggled with his shot at Summer League — he averaged 12.3 points and shot just 27.4% from the field and 20.5% from beyond the arc.

“It’s the same thing as a 4 or 5 game sample in December, January, February,” Reynolds said, adding: “It’s really nothing to get concerned about.”

Still, he helped set a tone from the jump that allowed the Summer League Celtics to win 4 of 5 games, and relish in an environment of joy.

“Baylor’s empowered me to lead this team,” Reynolds said.

On the court, the rising second-year player did everything else but score efficiently, tallying 6.8 assists and 5.3 rebounds per game across four Summer League contests. And, he’s turned the ball over just 1.8 times per game. Of players who have played in four or more games this July, Scheierman ranks second in assists.

“I just try to impact the game in every area,” Scheierman said. “I can’t control if shots are going in or not — I’m shooting to make it, I’m not shooting to miss… Being able to impact the game in whatever way is necessary is a good trait to have, especially when you’re with the big club, to stay on the floor.”

On Sunday, that included being the No. 1 hype man for an undrafted teammate he’d met just a few weeks earlier.