Spencer Dinwiddie's absence tests Nets' next-man-up mentality

Spencer Dinwiddie ran sprints after practice at the Nets’ training facility in Brooklyn on Sunday, but the hottest team in the NBA will have to survive without its offensive-minded Sixth Man of the Year candidate for the next several weeks.

On Monday, Dinwiddie will undergo surgery to repair torn ligaments in his right thumb and the Nets (27-23) will look to add to their 19-5 surge against the Celtics at TD Garden. Boston is 3 1/2 games above the Nets, who are in sixth place in the Eastern Conference standings.

“I think we view it as an opportunity to see where we’re at,” said guard Shabazz Napier, who scored 18 points in 28 minutes in Dinwiddie’s absence in Friday night’s win over the Knicks. “We do that with every single team no matter if they’re the last team in the Eastern Conference or the first team. We love the mindset of always challenging each other and always challenging ourselves.

“It’s just next guy up. We’ve been doing it the whole entire year, just continue to be prepared for that moment and the opportunity that’s coming before you. Hopefully myself and the others . . . can be able to provide some of what  [Dinwiddie] delivers for the team.”

Dinwiddie, 25, who wasn’t made available to the media on Sunday, is averaging a career-best 17.2 points and 5.0 assists. A finalist for the NBA’s Most Improved Player award last season, the fifth-year guard signed a three-year, $34-million contract extension last month. But he  had been playing through the injury for at least two months before deciding to undergo surgery.

“We’ve all been in medical situations, and those aren’t easy decisions,” Nets coach Kenny Atkinson said.

With Dinwiddie expected to be sidelined for three to six weeks, Napier will see extended minutes off the bench behind starting point guard D’Angelo Russell, who has played his way into All-Star consideration since Caris LeVert suffered a dislocated ankle on Nov. 12. Undrafted rookie Theo Pinson was called up from the G League and scored a team-high 19 points against the Knicks.

“Listen, we’ve found some gems . . . and through the course of these injuries, have found some other solutions,” Atkinson said, mentioning rookie forward Rodions Kurucs and others. “Like D’Angelo stepped up when Caris went out, too, we’ve somehow managed to fill the gap and be resilient and we’ve just got to do it again. I’m just trying to look at it in a positive light, but obviously I feel terrible for Spencer, because he was playing great.”

Notes & quotes: Rondae Hollis-Jefferson received four stitches below his right eye after Friday’s face-to-face collision with Knicks forward Noah Vonleh. He also has missed time this season with adductor and shoulder injuries. “Man, it’s been a roller coaster, just going through these little nicks and knacks, these little injuries. It’s definitely tough, more so on the mental side,” Hollis-Jefferson said . . . Atkinson said Allen Crabbe, who has been out since Dec. 12 with a knee injury, “did a lot of stuff today” and is “going in a good direction.”