After building a big third-quarter lead against the defending NBA champions, the Milwaukee Bucks poured it on in the fourth as they stunned the Cavaliers 118-101 on Tuesday night

But perhaps the most remarkable passage of play came when the Bucks exploited JR Smith’s affable nature for an easy dunk in the second quarter. Right before an inbound play, Milwaukee’s Jason Terry stood up off the bench to say hello to Smith, sharing a handshake and hug along the baseline. Smith was supposed to be covering Tony Snell, but with Smith mingling, Snell cut to the basket, received the inbound pass and dunked with nobody around.

J.R. Smith is a national treasure. Dude stops to talk to Jason Terry and allows the easy dunk...https://t.co/u07jVGJvIE — Def Pen Hoops (@DefPenHoops) November 30, 2016

Terry said it wasn’t planned and he didn’t realize play had restarted, and Smith at first said he just wasn’t paying attention. When asked again, he said, “I didn’t even know I was in the game. My bad.”. The interview was made more memorable by the fact that Smith was dressed in a ski-mask. “It’s my alter ego,” Smith said. “It’s a gift from Ohio State, so I figure why not?” Smith had attended the Ohio State-Michigan game last weekend.

J.R. Smith and his "alter ego" make a postgame appearance. pic.twitter.com/5vyGxeTjir — Dave McMenamin (@mcten) November 30, 2016

The Cleveland Cavaliers pulled their starters, including LeBron James, midway through the final period, but the young Bucks still didn’t let up.

“We didn’t let them off the hook. We were attacking,” said Giannis Antetokounmpo, who tied a career high with 34 points. “They are the champs, but this is a great win.”

Bucks coach Jason Kidd had high praise for Antetokounmpo, who was often matched up against James. “He’s getting better with hard work,” Kidd said. “He was going against the best player in the world.”

Antetokounmpo added 12 rebounds and five assists while Milwaukee ended Cleveland’s four-game winning streak. Jabari Parker had 18 points and Michael Beasley had 17 off the bench for the Bucks.

“It was a matter of us trusting each other,” Kidd said. “For a young team, sometimes it takes time. You want to put it in the microwave and instantly get it right away, but if you’re patient enough for the process and the journey, it will come.”

James had 22 points for the Cavaliers, who fell to 13-3. Kyrie Irving added 20 points. “You can’t simulate how long they are in the passing lanes,” James said. “But four of my seven [turnovers] were unforced and that’s careless.”

The Bucks scored a season-high 68 points in the paint. “They played harder than we did,” Cleveland coach Tyronn Lue said.

The Bucks outscored Cleveland by 14 points in the third quarter and led by 22 in the fourth. Cleveland rode hot early shooting to a 14-point first quarter lead, but Milwaukee closed on a 10-0 run and trailed by only two at the end of the period.

Antetokounmpo and Beasley sparked Milwaukee in the second quarter as the Bucks built an advantage of eight points before leading 58-54 at the half.