CLEVELAND — As Isaiah Thomas’ phone kept buzzing, his mind continued wandering on the eve of the most anticipated comeback to this NBA season. This was the culmination of the biggest test of his career, from the moment he had started rehabilitation for a serious hip injury to the phone call he received from his old general manager notifying him that the Boston Celtics had traded him to the Cleveland Cavaliers.

Thomas recovered from the torn labrum in his hip over seven months, bypassing surgery and putting his body through the rigors of rehab. The rust on Thomas’ game Tuesday night inside Quicken Loans Arena was noticeable yet minimal, with a 17-point, three-assist performance in 19 minutes in the Cavaliers’ 127-110 victory against Portland. He shot 6-of-12 from the field and made three 3-pointers, showing the ability to find his spots on the floor and the lift on his jump shot that have made him a two-time All-Star and an All-NBA performer.

For someone seven months out of the game, seven months removed from an injury that created external doubt and pressures, this was everything. He had targeted the start of the new year to make his season debut, a fresh start to his Cleveland chapter: IT’s 2018.

“I couldn’t sleep last night,” Thomas told Yahoo Sports. “This was a crucial moment for me to step foot on the floor. New team, new arena … I’ve felt like I didn’t know what to expect, what it felt like to be on an NBA court. I felt like a rookie. Not being on the floor in seven months, I haven’t had a rhythm. Today, it felt like I had a rhythm. I’m still rusty, but I feel good, I feel comfortable out there.

“Once I took that first shot, it felt normal again.”

Thomas entered his first game in Cleveland the same way he has always played, attacking the opponent, which featured the return of Trail Blazers All-Star Damian Lillard. Thomas is still searching for his flow, his fluidity on the court, but gave glimpses of the dynamic scoring ability that made him an elite player and a top star in the league on a given night. In truth, even one game in, he couldn’t wait to be unleashed.

There were the five shots in his first 4:33; the technical foul drawn late in the second quarter; the old off-ball screens against 7-footers and falls to the floor in which he never showed fear in Boston; and attempting to talk Cavaliers coach Ty Lue into extending his minutes Tuesday night. Both Thomas and the Cavaliers discussed his return off the bench, partly for him to receive an ovation from a soldout crowd. They’ve set a 20- to 22-minute restriction for him initially — one he tested on Tuesday, and one that he could play himself out of altogether, possibly as soon as his first start of the season Saturday in Orlando.

“It’s motivating to show I can break out of the limits, I hope,” Thomas told Yahoo Sports. “I know I can play so much better when that opportunity comes, and I’ll be ready to soon.”

So when those messages came flooding to his phone late Monday, Thomas responded. Some from former teammates. Some from his closest friends. But one came from Minnesota’s Jamal Crawford, a close, longtime friend and mentor who shared several long conversations with the fellow Seattle native during his rehab and recovery.

“IT is one of the very few people who I know that love hoop as much as I do,” Crawford told Yahoo Sports. “There’s never been one time that I’ve texted him, or vice versa, like, ‘Let’s go hoop,’ and one of us said no. For someone like that, who is watching every game no matter who’s playing, very few people could understand how this wore on him mentally. He already doesn’t take the game for granted, but this has helped him appreciate playing even more. Which is scary.”

When they shared messages last night?

“He couldn’t sleep, he was like a kid the night before Christmas,” Crawford told Yahoo Sports.

Seven months of rehabbing his injured hip, and Thomas accomplished Step One of a multi-step journey. Within the Cavaliers, there’s confidence in Thomas elevating the roster, and especially in co-existing with LeBron James when it matters most: in a potential NBA Finals against Golden State. Those questioning their ability to mesh have downplayed the brilliance of James and his talent to bring teams together as a season progresses.

There’s work to be done, though, and now Thomas awaits his journey to Boston, to his old Celtics teammates and GM Danny Ainge. It’s where he and Jae Crowder deserve loud ovations for their parts in rejuvenating the historic franchise, before the Celtics’ free-agent signing of Gordon Hayward and blockbuster trade for Kyrie Irving.

Thomas had his family behind him and his son, Jaden, beside him as he smiled on his postgame walk out of the arena.

“We show what we can be,” Thomas told Yahoo Sports. “It’s a process for me and I’ve got to trust it.”

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