Last May, Tyronn Lue raised a few eyebrows by proclaiming J.R. Smith — the famously flighty and monstrously mercurial shooting guard who never met a shoelace he didn’t dream of untying or a contested jumper he didn’t absolutely love — the “best defensive player” on last year’s Cleveland Cavaliers. I’m not so sure Ty will be singing the same tune after Tuesday night’s game against the Milwaukee Bucks, which featured perhaps the most quintessentially J.R.-y play of all time.

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With just under three minutes remaining in the second quarter of the Cavs’ Tuesday night visit to BMO Harris Bradley Center to take on the Milwaukee Bucks, Smith took a moment to head over to the end of the Buck bench to say hello to fellow veteran shooter Jason Terry. Generally speaking, a handshake and a hug between old pals isn’t super out of the ordinary. You don’t often see it, however, while the game is going on:

As Smith embraced Terry, Tony Snell — the man J.R. was supposed to be defending — realized that he was suddenly all alone in the corner, and immediately cut along the baseline toward the basket, demanded the ball, and threw down a couldn’t-be-easier two-handed dunk to push Milwaukee’s lead to three points. And you wonder why LeBron doesn’t let J.R. out of his sight.

The best part of it, for my money? How Kyrie Irving and Iman Shumpert just throw their hands up in stunned shock, as if they couldn’t possibly fathom what just went down:

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Actually, no. Come to think of it, the best part is still when J.R. just left the court as the game was going on to go dap up Jason Terry — a dude, by the way, that he elbowed straight in the jaw during a 2013 playoff series, earning a suspension and effectively submarining the rest of his postseason. JET must be a Lannister.

As of press time, the scorekeeper had yet to tally an assist for Terry on the play. I imagine they’ll update that later. Fair is fair, after all.

What was unfair — if you’re a Cavs fan, at least — is what the Bucks did to the defending champs after halftime. Jason Kidd’s club blew Cleveland’s doors off in the third quarter, ripping off an 18-2 run over a 5 1/2-minute span that turned a tie game into a rout.

The Cavs looked sluggish and the hungry young Bucks took advantage. They took aim at the throne and hit their mark, scoring a convincing 118-101 victory behind a stellar second-unit effort led by the immortal Michael Beasley, and another All-World-Everything performance from Giannis Antetokounmpo:

Milwaukee’s emerging star once again led the way, scoring a game-high 34 points on 13-for-19 shooting to go with 12 rebounds, five assists, five steals and two blocks in 34 1/2 minutes of scintillating work. LeBron James, Kevin Love and Kyrie Irving all suited up on Tuesday, but the 21-year-old Greek marvel was the biggest difference-maker on the court on this particular night, tying a career high in points while becoming just the third player since 1983 to put up a 30-10-5-5 before his 22nd birthday … and the first since a certain King turned in such a performance nearly 11 years ago (against the Bucks, natch).

On top of his stunningly viral defensive lapse, Smith scored just six points and missed five of his seven field-goal attempts on the night, continuing a shooting slump that had seen him go just 1-for-22 over his past two games. After the game, though, Smith’s dereliction of defensive duty was the thing everyone wanted to talk about … so, naturally, J.R. donned a balaclava, pulled his hood over his head, and decided to make the whole thing even weirder:

In the storied history of explanations for why you wandered off to go hug somebody while the other team was dribbling the ball up the court, perhaps none has ever rung as true or so satisfactorily answered the question as J.R. Smith muffle-dissembling through a ski mask the sentences, “Oh, I didn’t even know I was in the game. My bad.”

Yes, he lost on this particular play and the Cavs lost this particular game. But who among us can convincingly argue that, by prioritizing friendship and choosing to move through life chasing his bliss come what may, J.R. Smith isn’t the greatest winner of all?

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Dan Devine is an editor for Ball Don’t Lie on Yahoo Sports. Have a tip? Email him at devine@yahoo-inc.com or follow him on Twitter!

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