The Oklahoma City Thunder beat the Denver Nuggets at their own game Sunday.

The NBA’s youngest team made all the clutch plays in crunch time against an experienced squad teeming with a championship pedigree, knotting the second-round series with a 92-87 win in Game 4.

Shai Gilgeous-Alexander scored nine of his 25 points in the fourth quarter, pulling the top-seeded Thunder from the brink of a 3-1 deficit against a Denver team known for closing out games while winning six of its last seven playoff series — and the two tight games earlier in this series that resumes Tuesday in Oklahoma City.

About 36 hours after an exhausting overtime Game 3 Friday night, the early Mother’s Day tip-off produced an ugly first half that featured a combined 25 points in the first quarter and ended with OKC up 42-36 at the break.

Down by eight points early in the fourth quarter, the Thunder used an 11-0 run fueled by reserves Cason Wallace, who had a pair of 3-pointers, and Aaron Wiggins, who added another, to wrest control.

Wallace’s second 3-pointer put Oklahoma City ahead for good at 75-73.

Denver looked poised to put the top-seeded team in the West on the cusp of elimination when Aaron Gordon made it 73-66.

This time, however, it was the Thunder who came up big down the stretch and the Nuggets who fumbled away the chance to put OKC in a 3-1 hole. Nikola Jokic had 27 points and 13 rebounds but his three assists were a low for this playoff run and gave him 22 assists to go with 23 turnovers in the series.

Pacers 129, Cavaliers 109: Pascal Siakam scored 21 points and Indiana tied an NBA playoff record by taking a 41-point halftime lead before routing top-seeded Cleveland for a 3-1 lead in the Eastern Conference semifinals.

The Pacers can earn a second straight trip to the East finals with a victory Tuesday in Cleveland, where they won the first two games.

Indiana jumped to an 80-39 lead at halftime.

And Indiana did it mostly without Bennedict Mathurin, one of its top playoff scorers, who was ejected just 7 1/2 minutes into the game for a flagrant foul.

Darius Garland led the Cavs with 21 points and Donovan Mitchell had 12 points despite not playing in the second half because of a left ankle injury.