For ageless Nowitzki, clutch has no expiration date

Dirk Nowitzki celebrates a 3-pointer in overtime against the Celtics on Monday.

Jerome Miron/Jerome Miron-USA TODAY Sports

Around Dallas these days there’s a popular phrase repeated every time Dirk Nowitzki has a vintage performance like Monday’s 31-point, 11-rebound, super-clutch effort that beat the Boston Celtics in overtime, 118-113.

The phrase: He’s still Dirk Nowitzki.

Those types of performances don’t occur as often they once did, but they certainly occur more often than anybody probably believed they would at 37 years old — and by far more than any other player in his age group.

You don’t have to tell the Celtics that Dirk is still Dirk. He entered the game with a career average of 25.9 points against them, his highest average against any team. By the time he swished a corner 3-pointer for his 21st point of the fourth quarter and overtime, his career average against Boston hit an even 26.0.

““They played in their zone and we prepared for that,” Nowitzki said afterward. “I just saw nobody on me and I popped straight back and the man was supposed to rotate back to me and Zaza (Pachulia) set a screen and I was able to knock one down.”

Nowitzki, in his 18th season, is headed toward a 14th All-Star selection. He’s averaging a team-best 17.8 points a game and is shooting 39.8 percent from beyond the arc. He’s second on the team in rebounding at 6.9, just one off his career average.

His scoring average is No. 1 among players 35 and older. But it’s when he’s scoring that is probably most impressive. The NBA tracks clutch stats, which are points during the fourth quarter or overtime, with less than five minutes remaining, and neither team ahead by more than five points. In other words, when games are won and lost.

Nowitzki, averaging 30.9 minutes a game this season, ranks ninth in the league in clutch scoring average and fifth in total clutch points with 88. That’s two more clutch points than LeBron James, three more than Russell Westbrook and 14 more than Kevin Durant. Of course, clutch points will depend on how many clutch moments a team is in, and the Mavs and Nowitzki have been in more games down to the wire than the players mentioned above.

Still, it hardly detracts from what Nowitzki is accomplishing in the twilight of his career. Of the four players with more total clutch points, none is older than 26. Of the eight players with a higher clutch scoring average, James, 31, is the oldest. Nowitzki’s shooting percentages in the clutch (49.1 from the floor and 41.7 on 3s) are better than his overall numbers.

Almost every player selected in the first round of the 1998 draft is long out of the league. Those who aren’t, such as Paul Pierce and Vince Carter, are finishing up their careers as role players.

Nowitzki remains in a starring role. And, in fact, as hard as the Mavs have tried to bring in another elite-level player to reduce his burden, Nowitzki is inarguably the best player on his team again, and the key reason why the Mavs sit fifth in the Western Conference with a 24-18 record.

Down the road in San Antonio, Tim Duncan, who will turn 40 in the first round of the playoffs, continues to defy Father Time. He has been able to enjoy a talented and remarkably stable roster around him that has afforded him both an easing of responsibilities and minutes.

Conversely, the Dallas roster has been a revolving door since the Mavs won the 2011 championship. Each season has seen almost an entirely new cast of characters requiring a total adjustment.

Only Nowitzki never changes. His true shooting percentage — which takes into account 2-pointers, 3-pointers and free throws — is a robust 56.2 percent. Of players 35 and older, six players have a higher percentage, and all are reserves. Two have played in a combined 36 games. Nowitzki has played in 40. One, Manu Ginobili, averages 20.2 minutes. None of the others average more than 17.1 minutes.

So, yeah, he’s still Dirk Nowitzki.