Danny Ainge’s playful interaction with Marcus Smart Monday night in Las Vegas was the first between the Celtics’ free agent guard and the team’s president of basketball operations. Adam Himmelsbach

LAS VEGAS — Around the time the Celtics completed their summer league win over the Hornets on Monday night, guard Marcus Smart took a front-row seat in Cox Pavilion for the following game between the Nuggets and Bucks.

Smart remains a restricted free agent looking for a contract for next season, and his interactions — or lack thereof — with the Celtics, have been somewhat uncomfortable for both sides since the season ended.

On Monday night, Celtics president of basketball operations Danny Ainge spotted Smart, and as he walked down the aisle behind him, he playfully twisted the black baseball cap on Smart’s head. Smart initially did not know who was messing around with him, and when he turned and saw that it was Ainge, both of them briefly smiled before Ainge continued down the aisle and left the gym.

It is believed to be their first interaction during this somewhat uncomfortable process, and while it was hardly a contract negotiation, it was something. A source close to Smart told the Globe on Friday that Smart was hurt by the Celtics’ lack of communication with him during this process.

On Monday, about 30 minutes after crossing paths with Ainge, Smart had a brief interview with the Globe and The Athletic as he walked from the Nuggets/Bucks game to watch the Suns face the Magic in an adjacent arena. When asked where things stood with the Celtics, Smart responded: “That’s what I want to know. I have no clue. I can only control what I can control.”

Smart is a restricted free agent, meaning the Celtics will have the ability to match any offer sheet he signs with another team. League sources have insisted that the Celtics plan to match just about any offer Smart receives elsewhere, but very few teams currently have the cap space needed to make a sizable pitch.

Smart could also sign the Celtics’ one-year, $6 million qualifying offer, which would make him an unrestricted free agent after next season.

When Smart was asked about whether there were indications that an offer sheet from another team could be coming, he said that he believed he would find out soon.

When he was asked if he was optimistic that he will receive a big offer, he responded simply, “I don’t know.”

Smart was then asked whether he hopes that this situation would be resolved quickly.

“I do,” he said. “But I can control what I can control.”

Celtics coach Brad Stevens, who exchanged brief pleasantries with Smart when they crossed paths in a crowded area near the bleachers after the Celtics’ game, reiterated that the franchise’s desire to bring Smart back next season has not dissipated.

“Marcus is, I think, pretty well aware of how I feel,” said Stevens. “I saw him a couple days before free agency. He was in town for his camp. I saw him over at the new practice facility. I’ve talked to him a bunch. I’m not involved in all the negotiation part of it and all the numbers part of it, and he knows that. He also knows we really want him back. So I know our front office has worked hard to be communicative, and go from there.”

It still seems likely that Smart will return to the Celtics next season. If he re-signs, that would leave Boston with just one open roster spot. The Celtics could use at least part of the mid-level exception to sign another player, or they could stay at 14 players to maintain better roster flexibility at the start of the season.

It is most likely that Boston’s focus will simply shift toward the deep, talented team it has already assembled, especially the healthy returns of injured starters Gordon Hayward and Kyrie Irving.