The Portland Expo was alive with the sounds of bouncing basketballs, squeaking sneakers and echoing hand claps on Monday afternoon.

The Maine Red Claws are back in town.

Second-year head coach Scott Morrison conducted the first practice of a 10-day training camp leading to the start of the NBA Development League season. Coming off the best record in franchise history, the Red Claws open their schedule on Nov. 12 in Westchester, New York. Their first home game is Nov. 20 against a new franchise, Raptors 905 from Toronto.

“I could probably coach for another 30 years and maybe not have as successful a year as we had last year,” said Morrison, who coached in the D-League all-star game and coached the D-League Select Team in the NBA Summer League in Las Vegas. “We’ll just try to start fresh and keep my favorite motto in mind, that if you’re still thinking about what you did yesterday then you haven’t done much today. Hopefully, we can accomplish something today.”

Fifteen players worked out at the refurbished Expo, with a 16th scheduled to arrive in time for Tuesday’s action. Morrison said he hopes to trim his roster to 10, with an inactive player or two in reserve, following Sunday’s Red-White scrimmage at the Expo. The scrimmage, with free admission, begins at 6 p.m.

Most of the faces on the court Monday were new ones. The exceptions were Omari Johnson, Andre Stringer and Ralph Sampson III, all key components of a Red Claws team that won at a .700 clip last season (35-15) to earn the top playoff seed and Morrison Coach of the Year honors.

“Obviously, the camp I was in was my first choice,” said Johnson, waived by the Portland Trail Blazers late last month after appearing in four preseason games with the NBA club. “But it’s not a bad second option to come here.”

Johnson was one of three former Red Claws in camp with the other Portland. Tim Frazier, the D-League MVP last season, beat out former Celtic Phil Pressey (who dropped 34 points in his one appearance in Maine) for the job of backup point guard with the Blazers. Pressey caught on with the Idaho Stampede, Utah’s D-League affiliate.

Stringer, a crowd favorite as much for his deadly 3-point shooting as his just-like-us height of 5-foot-10, planned to play in Europe this season but spent only a week in Poland in September before returning home.

“Some things happened with my physical and I wasn’t able to stay,” Stringer said. “I’m great physically. It was a good experience.”

Sampson, another fan favorite because of his willingness to set picks, guard bigger players in the post and even dive for loose balls despite his 6-11 frame, played summer league ball in Las Vegas and Utah with the Celtics and worked out at his home in Atlanta with younger brother Robert, a 6-8 slasher who played briefly in Argentina after playing college ball at Georgia Tech and East Carolina.

“The main motivation in coming back here was the season we had last year,” said Sampson, referring to the bond formed between players, coaches and fans. “I feel like the three of us who are here now, we definitely have a bond from last year and having that bond will spread throughout the team.”

Of course, it won’t be the same because most of the roster will be different. Still, the Claws will be a team that passes unselfishly, works hard on defense and rains down 3-pointers, ideally after first driving into the paint to draw in defenders.

“I feel people will see the same energy and the same principles that we had last season,” Sampson said.

Aside from the veteran trio, the core of the Red Claws is likely to be a quartet of affiliated players invited to training camp with the parent Celtics: guards Corey Walden and Levi Randolph and forwards Coty Clarke and Malcolm Miller.

The Claws also picked up five players in (or shortly after, via trade) Saturday’s league-wide draft: Kevin Young, Karrington Ward, Ella Ellis, Jermaine Marshall and Brett Olson. Ellis is an intriguing selection. He hasn’t played organized basketball since graduating from West Point in 2013.

“He had a good career at Army and he’s got the right size and skill set for what we’re looking for,” Morrison said. “We’re guessing that he’s going to be a high-character, hard-worker type, so that’s always a plus. We’ll see what he can do.”