One of the several ways he was notified that he wasn't on a college campus anymore last season was when he drew the assignment of defending Shaquille O'Neal.
"You get tired after awhile," Powe said of guarding the Miami Heat's 7-foot-1, 325-pound giant of a center. "He tries to wear you down. He won't try to score during that first post-up. He'll throw it back out and then bury you under the rim."
Powe recently completed an uneven rookie season that began with him buried on the end of the bench but ended with him as an integral part of the Celtics' playing rotation. Powe took advantage of a litany of Celtics injuries to earn playing time and started to earn respect around the league in the process.
Along the way, Powe found out what it's like to be a professional athlete. He said the differences between college and the NBA are not that dramatic on the court. It's off the court where the adjustment lies.
"You have to watch who and what is around you," Powe said. "Some people might not have the right intentions or might try to sell you something that isn't legit. It's happened to me a couple of times."
Powe is perpetually upbeat, so he welcomed the challenge of the pro game. His explanation is simple: "I like to play basketball."
But in the NBA, he played more basketball than ever before.
Powe admitted the 82-game season was an adjustment, especially when the Celtics endured a franchise-record 18-game losing streak. Eighteen games is a full Pac-10 season.
"I was joking with myself that (the losing streak) was like a whole college season," Powe said. "The season is kind of long, especially in practice. You are doing the same thing over and over again, and you realize you have 82 games."
While Powe had experienced the rigors of travel during his days at Cal, he'd never done anything like the travel required of an NBA player. Powe said he enjoyed visiting different cities and learning about their history and culture. His rough upbringing in Oakland was pretty insulated; he didn't get much of a chance to see the world outside of his neighborhood.
"I don't think I even went to San Francisco until I was about 15 or 16," Powe said. "I try not to take anything for granted. Without basketball, I wouldn't be able to see anything. I try to take advantage of it."
Of course, it's easier to enjoy traveling when you're treated like a VIP. NBA teams fly on charter planes. The team bus drives onto the tarmac for boarding. Players are accorded spacious seating.
"That is unreal," Powe said. "I fall asleep every time and don't wake up until we reach our destination."
One of the biggest changes in Powe's life now that he's an NBA player is financial freedom. Powe hasn't had much for most of his life, but he was due to make about $460,000 this season. With the help of his unofficial guardian, Bernard Ward, Powe met with a financial advisor to set up a monthly spending allowance. He also received advice from Golden State Warriors center Adonal Foyle.
Powe, who is fiercely loyal to his simple roots, hasn't spent lavishly. Ward had to encourage Powe to buy a watch because he didn't own one. Powe's one big expense so far was a vacation he recently took to the Bahamas with his girlfriend, Lauren Cook.
"He doesn't see (basketball) as more of a business now, but it's his job now, and he's getting paid," Ward said. "He's become a mature man who knows how to take care of his business."
Powe also has more free time than before. But he's not living the high life. He said he spends most of his spare time going bowling or attending movies with Cook.
Powe also believes he should use his position to get involved in the community. As a Cal student, he talked to children about the importance of education. He's doing the same thing in Boston. Cook is as well, working in an after-school program for underprivileged kids.
Powe is going to spend most of this month in the Bay Area, and he is planning more charitable work while he is here.
"He feels like it's his job to give back to the community," Ward said. "He wants to talk to kids because he knows he can teach them. He feels like it's a big responsibility. Leon is the same guy he always was -- so humble, so down to earth."
Powe feels confident he is a big part of the Celtics' future. It took him awhile to get down the pace and demands of an NBA season, but he's reached a comfort zone.
"The NBA is much more demanding. You have to know your stuff," Powe said. "They expect you to pick up on things right away. I feel good about things, but I have to keep working. I have to make sure I come next season even more prepared."
Contact Jonathan Okanes at firstname.lastname@example.org.
THE POWE FILE
About the series
The competition gets tougher and the stakes get higher each time an athlete advances to the next plateau, but nowhere is that more evident than when he turns pro. This series looks at three players with local ties who recently learned that lesson for themselves.