BOSTON — The alarm clock-style "3:17" tattoo on the back of his head served as a reminder of his upcoming birthday and, in the days leading up to turning 25, Terry Rozier turned slightly introspective. He’s old now, he joked, and he was pretty sure you skip right to 30 after this.

Still, he had big plans for his birthday, aided by a rare matinee start for the Boston Celtics the day before, which allowed him an extended night on the town with friends. Rozier knew that, amid the night’s festivities, a familiar text would arrive shortly after midnight from Celtics president of basketball operations Danny Ainge.

“He’s always usually the first one to send me a happy birthday text, too. Every year,” said Rozier. With a smile, he added, "We’ll see how he acts this year.”

Rozier and Ainge are maybe the NBA’s oddest of odd couples but they have bonded over more than just a shared St. Patrick’s Day birthday (highly appropriate for members of the Celtics organization). Despite their very different backgrounds and the 35 years that separate them, Rozier and Ainge have forged a unique bond, one that’s been tested by the business side of the NBA this season. And that’s why Rozier playfully wondered if Ainge would still be the first to text a birthday greeting this year.

"I know he had some thoughts about trading me this year,” admitted Rozier. "I respected the business side of it. I don’t ever try to get too much in other people’s jobs. I try to do my job, which is on the court. Like I said, I know he had thoughts, but it didn’t happen.

“Obviously, we’ve got some similarities. You know it’s pretty dope to have a guy around, especially a GM that played in this league, stuff like that. Our relationship is good. Sometimes, you know, a lot this year, I’ve wanted to put on the gloves with him, feel like we need to fight sometimes.”

The past 12 months have been wild for Rozier. When Kyrie Irving’s season ended last March due to a balky knee, Rozier stepped into a starting role for the Celtics and made “Scary Terry” a household name, which included a starring role in Boston’s unimaginable playoff run. Rozier averaged 16.5 points, 5.7 assists, and 5.3 rebounds while starting 19 postseason games. A first-round flareup with Bucks guard Eric Bledsoe helped launch Rozier to a new level of celebrity.

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The rest of the NBA took notice. A huge payday seemed to loom in the summer of 2019 when Rozier reached restricted free agency. Despite a high trade value, Ainge and the Celtics elected to bring back Rozier, believing he was a key piece of their core, even with Irving back at full strength.

Like many on Boston’s young playoff standouts, Rozier has struggled to figure out how to harness his postseason success in a diminished role. He’s put up modest numbers — 9.1 points, 4 rebounds, 3 assists while averaging 22.9 minutes per game — off the bench but his struggles to positively impact the team in a reserve role have been well documented, and some of the blame for Boston’s inconsistent ways has been directed at Rozier.

Still, Ainge resisted any lingering urge to move Rozier at the deadline — in part because his postseason potential was higher than his trade value at that point — and despite all the rumors, Rozier took it as a vote of confidence that he’s still in green.

"You can have thoughts all you want but he didn’t [make a trade],” said Rozier. "I’m still glad to be a part of this organization and be a part of something great. I’ve got no complaints.”

There is an undeniable bond between Ainge and Rozier, strengthened by their confidence they’ve long had in one another. Some projected Rozier as a late first-round pick at best and many were surprised when the Celtics used the No. 16 pick in the 2015 draft to select him after two seasons at Louisville.

Ainge had made a well-publicized push to acquire a mid-lottery pick that year with the team seemingly hellbent on getting in position to nab Justise Winslow. They were rebuffed in their efforts and Ainge would later admit that maybe that was a good thing considering the picks the team nearly splurged to shuffle up a handful of spots.

The day after the draft, Ainge woke up invigorated by the Rozier selection. The first of three picks that Boston made in the top 33, Rozier had wowed Boston with not only his speed and athleticism but his desire to get better. Ainge scoffed when draftniks suggested he reached for Rozier at 16.

Rozier’s breakout last season validated Ainge’s pick. And the bond between player and GM was strengthened by that faith. Ainge often gushes about the way Rozier plays the game and his overall swagger.

Where else does an NBA general manager wonder out loud if he could get “one drop off that drip.” And where else could a player FaceTime his GM during a live draft broadcast and get him to (unknowingly) reveal the team’s upcoming selection (Robert Williams). Ainge was able to laugh off the incident in the aftermath, but it showed a little window into this player/GM relationship.

Rozier said the friendship has blossomed, in large part, because of how competitive both he and Ainge are. “He’s a super competitive guy; he likes to talk a lot of smack,” said Rozier. Before the season, Ainge brought Rozier into his office and made him watch highlights of Ainge’s playing days at a teaching tool.

Rozier feels comfortable around Ainge and feels like he can approach him about anything, including many non-basketball issues. With the spring approaching, Rozier is just waiting for Ainge to inquire about some Puma golf swag. Can Rozier make that happen?

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“I’ll hook him up,” said Rozier. “But he’s gotta take me golfing first.”

Rozier can’t golf but he wants to try (he’d like to try tennis, too, but that’s a story for another day). That golf outing will have to wait until after the season. There’s much work to be done before that.

And much of Boston’s playoff success could hinge on whether players like Rozier are able to find a bit of what made this team so successful. Ainge has unrelenting faith that Rozier can positively impact the game. He’s encouraged Rozier to block out the noise and focus on being the impact player we saw a year ago.

As he turned 25, Rozier took a minute to savor all that’s changed over the past year. And even though the future is murky, he’s putting all his energy and effort into the postseason that lies ahead.

"A lot of people that didn’t even know me a year ago. Little kids calling me Scary Terry, everybody knowing me in different cities. I’m super blessed,” said Rozier. “Obviously, a lot of people have high expectations, want me to score 26, 25 in 19 minutes, 18 minutes, that’s just part of basketball, fans don’t really understand things going on. Obviously, I could play a little bit better, I don’t never want to use an excuse, I’m not an excuse-making type person.”

The playoffs are a chance to remind everyone of the player that Rozier can be. Ainge has showed unwavering support and Rozier is hoping to reward it with the return of Scary Terry.

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