Still, Allen never came to the realization that the babyfaced guard was exactly half his age until a reporter informed him a couple of days later.
"Wow, I didn't know he was only 19," Allen said. "He looked very young. I'd imagine for him, it had to be intimidating, because I’m sure he’s watched me play for most of his life. This is my 18th year in the NBA. It’s crazy."
It is, and what's crazier is that he's still competing at this level—posting per-minute statistics, at age 38, that are virtually identical to those from his last season as a Boston Celtic and his first season with the Heat.
Allen is a stickler for regimen and routine, and it shows in his numbers: According to Basketball-Reference.com, he's averaging 5.2 made shots per 36 minutes this season, same as each of the past two seasons, while taking 11.3 shots per 36 minutes, two ticks down from last season (11.5) but the same as the season prior.
He's playing 25.7 minutes per game, compared to 25.8 minutes last season, and his points, rebounds, steals and turnovers per game, as well as his shot distribution and percentages, are all in line; the only discernible difference is he's dishing out an extra assist.
This consistency is striking in comparison to his former Celtics teammates, Kevin Garnett and Paul Pierce, both of whom have fallen off a cliff in their first season as Nets. Pierce, 36, is shooting 36.8 percent. Garnett, 37, is playing even fewer minutes per game than Allen, and all of his numbers—other than his rebound rate—are ugly.
What's Allen done to stay so steady?
Well, he's actually tinkered some, to get even lighter and fitter. He started the paleo diet in the offseason but has significantly adjusted his intake since the season started, adding two servings of carbohydrates, one in the morning and one in the evening.
"It’s helped me understand my eating a little better, and also know what my body is doing and when I feel depleted, I know I need more," Allen said. "It’s been good, because I’m not just eating carbs all the time. Now, first thing in the morning, I eat carbs. Then we have shootaround, and then I come back and have a salad and fruit. Then I have carbs before the game, and that’s it."
So, yes, he feels faster, and better, than in recent years. Improved health has helped: His ankle feels far more stable than it did early last season, when he was recovering from surgery.
"And even now, 18 years in, I really reinvented how I ate and how I took care of my body," Allen said. "I lift more now than I have ever lifted in my career. I never lifted on gamedays. I lift on gamedays now. Getting my body going, and getting my legs strong, and keeping my wind good.
"I always hated to be the person to say, 'I wish I knew then what I know now.' And I haven’t said that too often in my life. I’ve taken great care of myself, but now, I’m so much more meticulous to taking care of my body to make sure I give myself the best chance. I feel better, and it’s all because I push myself a little more when I have those opportunities."
As a result, he should have the opportunity to keep playing after this season, when his contract runs out.
But what about when he retires? How will he feed his competitive fire?
What about golf?
"I feel like there’s a misconception with golf," Allen said. "You can’t just play golf the rest of your career and feel satiated competition-wise. I’ve gotten my handicap down to the point (currently plus-1) where I could play professionally if I wanted to—I could try to compete."
He recently had a better idea.
"I was sitting on the couch when I was sick, and I was watching the Ironman in Hawaii," Allen said. "I was trying to think of every reason why this isn’t possible for me to do."
He quickly ran out of those reasons. His mother and wife have both run the Boston Marathon multiple times, and he had already intended to try that after he retired. The Ironman Triathlon requires a 2.4-mile swim, a 112-mile bicycle ride...and then a marathon, with no break in between.
"I saw Hines Ward on his bike," Allen said of the former Pittsburgh Steelers receiver, who completed the entire course in 13 hours, eight minutes and 15 seconds, finishing 1,680th. "And he had this grueling look on his face. I was thinking, two-fold, yeah, that looks tough on him. But then at the same time, he’s laying the groundwork. It’s great for me to be able to see him doing that, and putting the work out there."
Ward trained for an entire year.
"He hasn’t relied on the fact that he had a great NFL career, and everything that he’s done physically, he left it right there, he’s not pushing himself after his career," Allen said. "That’s what we have a tendency to do. Physically, we’re tired, and then you say, I don’t want anything physically anymore, I don’t want to push the envelope.
"That’s something I want to at least try and see how my body can withstand. Because the pounding here for us is tough, but when you just train regularly running, swimming and biking, I know that’s equally as hard. But it doesn’t take as much a toll bouncing up and down, bodies banging. So I want to see if I can accomplish that."
Erik Spoelstra, who calls Allen "Everyday Ray," knows better than to doubt Allen.
But when Allen told him about his intention on Thursday, Spoelstra wasn't sure about one element.
"He could do the running, he could do the bike," Spoelstra said. "He could train for that. But you have to really be conditioned as a swimmer. That is the real deal. That is a long way."
How's Allen in the pool?
"That’s my weak point right there," Allen said. "Can I overcome that and do something where I can really get a good time? I’ve swam my whole life, but I can’t say I’m a great swimmer. That’s going to require some work."
He said that with a smile.
Ethan Skolnick covers the Heat for Bleacher Report.