SAN ANTONIO (AP) -- It's a tense moment on the court and Tim Duncan is focused, watching one opponent out of the corner of his eye as he sizes up another.
Duncan suddenly pushes aside the charge of Cory Joseph and wraps up teammate Aron Baynes in a chokehold from behind, eliciting laughter that breaks the pressure.
There is always some mischief behind the steely gaze of the San Antonio Spurs' veteran forward. Always on the watch for a chance to prank or tease his teammates, Duncan is fully embracing another postseason with the only franchise he has ever played for.
''I always tell people Timmy is very funny,'' said Tony Parker, Duncan's teammate for 13 years. ''I know he is very quiet and doesn't talk a lot to the media, but with us it's a great relationship.''
After averaging 21.9 points and 12 rebounds in 15 previous postseasons, Duncan had 27 points and seven rebounds in 38 minutes during San Antonio's 90-85 victory over Dallas in the opener of their first-round series.
''It is always an exciting time and it is always a great time,'' Duncan said. ''I always look forward to a different intensity level. I might be even more excited now because I know there are only a couple more left in my career. I'm going to take the opportunity and really remember it.''
Duncan is having one of the finest seasons of his 17-year career. Perhaps it shouldn't be surprising, considering he is so young at heart even as he prepares to celebrate his 38th birthday Friday. The man who has won four NBA titles, two MVP awards and been a 14-time All-Star proudly confesses he loves reading comic books and playing video games.
''I enjoy jokes, smiling, and making people smile,'' Duncan has said. ''I may be a little different, but that's OK, who wants to be normal anyway?''
And Duncan is anything but ordinary.
He has only gotten better since winning NBA Rookie of the Year award in 1998 and the excellence showed up again Sunday against Dallas. He had nine points on 4-for-5 shooting in the final quarter as the Spurs rallied from a 10-point deficit with 7:45 remaining.
''He's a good player, a good finisher,'' Mavericks forward Dirk Nowitzki said. ''Duncan in there is obviously still solid. Both shoulders, good on the face up and he's good on the block.''
Teams have pushed Duncan back out of his comfort zone on occasion, forcing him to avoid his favored bank shot. So he has added a straightway jumper in the past few seasons and has been more active under the basket. He averaged 15.1 points, 9.8 rebounds, 3.0 assists and 1.9 blocks this season.
''There is nothing you can do,'' Portland star LaMarcus Aldridge told NBATv after a Jan. 15 victory over the Spurs. ''I know early in my career he gave me the blues. I think he scored 12 points straight on me my rookie year. I don't think it can get any worse than that.''
Aldridge called Duncan the greatest power forward of all time and many share that opinion. That Duncan has been able to sustain that success while playing nearly 1,500 career games following four years at Wake Forest is a tribute to his competiveness as well as to his commitment.
''How does Larry Bird make all those shots? The great ones just do what they do,'' San Antonio coach Gregg Popovich said. ''There's no magic formula. He works at it. He watches what he puts in his body. He works all summer. He never really gets out of shape. He's competitive. He loves basketball. He feels a responsibility to his teammates to stay as ready as he can. For all those reasons, he's been great.''
Duncan lost dropped more than 30 pounds over the last few seasons to lessen the wear on his aging body. Popovich has also helped by limiting Duncan to 29 minutes per game this season.
''If you've just observed him over the last four or five years, he's really changed his body,'' former Minnesota coach Rick Adelman said. ''He hasn't gotten bigger, but he hasn't lost any strength. He's leaner. He's quicker. He knows how to play. He's always known how to play. So you've got to give him a lot of credit for adjusting as he's gotten older.''
If the Mavericks are going to rebound in Game 2 on Wednesday, they must find a way to stop Duncan.
''We will look at all of that in the matchups,'' Dallas coach Rick Carlisle said. ''We have to make (Duncan) work for shots and keep him off the free throw line. It is a big part of the series. The free throw differential was big against them during the season and we have got to do a better job. He is one of the top 10 greatest players along with Nowitzki, so he is going to score some points. We have to evaluate our game plan and adjust it where we need to adjust it.''
The Spurs are expecting the Mavericks to make adjustments. That's fine with the defending Western Conference champions.
''If they change things up then we go back to Spurs basketball and ball movement,'' Parker said. ''Our shooters will make 3s, they made 3s all season long so I have confidence they will keep shooting like that.''