When Tim Duncan decided to reflect on his outstanding 19-year NBA career, the understated star did it in the most Timmy way possible: seated at a table with a friend.

Two days after the San Antonio Spurs announced his retirement, Duncan told longtime friend Rashidi Clenance that he simply "started not enjoying myself as much. It wasn't fun as much.

"When it's not fun anymore, I'm done."

When his decision was announced, Duncan was hailed as perhaps the greatest power forward the NBA has ever seen - a five-time champion and peerless teammate whose selflessness and determination formed the backbone of the most enduring success story in American sports over the last two decades.

Duncan tried to avoid much of the praise, watching former teammate Bruce Bowen's tribute on ESPN and coach Gregg Popovich's emotional news conference on Tuesday.

"I about lost it on that one," Duncan said during the interview streamed online.

"I didn't expect the response that I got," Duncan said. "No, I didn't. That's the way I'm built. I knew that I didn't want to sit there and watch what was being said. It's appreciated, but I just didn't want to watch it."

Duncan looked relaxed while doing the interview, seated at the table with a green T-shirt with a picture of Manu Ginobili and himself blocking out.

Duncan said there were no immediate plans for the next phase of his life, which is just the way he wants it.

"That's the beauty of it. There is no script," he said.

"For the first time in 20-something years, I don't have a script. I don't have somewhere I have to be and something I have to do. So, I get to go out and enjoy my kids even more.

"Outside of that, I get to do a little living."

Duncan has two children - son Draven and daughter Sydney - and for several years has had a side business in San Antonio customizing automobiles.

"I don't know that they were happy or sad," Duncan said of his children.

"I think they're OK with the fact that I'm going to be around more and they don't have to compete with the schedule or anything else. So, I think they're happy about it but they're sad that they won't be able to go to the games and see me play. It's mixed."

Duncan downplayed the significance of his career several times during the interview, consistent with his humble demeanor ever since he was the No 1 overall pick out of Wake Forest in 1997.

He said he never pays attention to comparisons between himself and other all-time greats.

"I don't really care where the rankings go," he said. "I'm in the conversation. I'm OK with that. That's above and beyond anything I ever thought I'd ever be. That in itself is an honor."

Duncan also penned an open letter to Spurs fans that was posted on the team's website and said he was taken aback by all of the fawning over the last few days.

"Luckily I'm not dying," he cracked. "I'm just moving to another chapter."

He grew emotional as the interview came to a conclusion.

"It's been fun," Duncan said, pausing to compose himself.

"The next chapter will be fun, too. I really enjoyed the ride. I really enjoyed the cheers and the laughs and the highlights and the lowlights, everything that comes with that package. No better way to put it than, 'Thank you."'