J.R. Smith of the Cleveland Cavaliers rebounds the ball after a missed free throw in the closing seconds of regulation in Game 1. You know what happened next. (Lachlan Cunningham/Getty Images)

Oh, J.R. Smith, what are we ever going to do with you? Before Game 1 of the NBA Finals, Golden State was so heavily favored against the Cleveland Cavaliers, bookies gave the Warriors -750 odds, meaning gamblers had to wager $7.50 just to win a single dollar back.

And yet there was Cleveland with a chance to steal Game 1 on Thursday night, thanks to Smith’s rebound four feet from the rim and a shot at a game-winning putback in the final seconds.

You’ve seen the replay of what Smith did instead by now: He dribbled the clock out like a fool. Golden State won the game in overtime. America collectively shook its head.

Just how badly did Smith screw up? Let’s put it in context with other championship-round gaffes, starting at least severe and careening to most cringe-worthy.

Leon Lett’s Super Bowl fumble

The Cowboys came up with a strip sack late in Super Bowl XXVII against the Buffalo Bills, and Lett, a defensive lineman, scooped up the loose ball and ran footloose and fancy free toward the end zone. But he slowed to celebrate upon approaching the goal line, and Buffalo’s Don Beebe knocked the ball out of his hands at the 2-yard line. It rolled through the end zone for a touchback.

It was a horrifically embarrassing play for Lett, one of two fumbles that still define his 11-year career. But the Cowboys were up big at the time, and the play didn’t affect the outcome of the game.

Fred Brown’s pass to James Worthy

Georgetown and North Carolina went down to the wire in the 1982 college basketball national championship game. Michael Jordan hit a jump shot with 15 seconds to put the Tar Heels up 63-62. Fred Brown, the Hoyas’ point guard, rushed the ball downcourt and faked a pass to the wing that drew North Carolina’s James Worthy out of position. But it also confused Brown, who threw a chest pass directly to Worthy, who ran the clock out.

Chris Webber’s timeout

Another great break for North Carolina basketball, this time in the 1993 national championship game. With the Tar Heels up two and 15 seconds left, Chris Webber grabbed a rebound for Michigan and, after appearing to get away with traveling, dribbled directly into the teeth of North Carolina’s defense. He panicked and called timeout when the Wolverines didn’t have any remaining, the penalty for which was two free throws for North Carolina, plus the ball. The play continues to haunt Michigan basketball.

Through Bill Buckner’s legs

Even if Boston’s first baseman had fielded Mookie Wilson’s slow-rolling groundball in the 10th inning of Game 6 the 1986 World Series, the score was tied and would have rolled into the 11th. But instead, the ball scooted through Bill Buckner’s legs, and the winning run scored.

J.R. Smith?

This spot in the rankings should tell you how severely Smith screwed up. Cleveland is such an underdog in this series that stealing Game 1 on the road would have turned the entire NBA Finals on its head. Let’s recount all the things Smith could have done but didn’t do: SHOOT THE BALL immediately upon getting the rebound, pass to a wide-open LeBron James at the top of the key, call timeout, take a three-pointer, pass to a wide-open Jeff Green on the wing.

Smith, of course, did none of these things and in the process wasted a 51-point outing from James and spoiled Cleveland’s best shot at a road win.

Jackie Smith’s Super Bowl drop

The difference in Super Bowl XIII was that the Cowboys settled for a field goal instead of a touchdown on one scoring drive against the Steelers. Why were they forced into that field goal? Jackie Smith’s infamous drop. On third and three from the 10-yard line, Roger Staubach had Smith wide open in the middle of the end zone. Maybe Smith was too wide open. He couldn’t haul in the pass. Dallas took three points. Pittsburgh won, 35-31.

The Seattle nightmare

Super Bowl XLIX. Seahawks ball on New England’s 1-yard line. Twenty-five seconds left. Running back Marshawn Lynch in the backfield. Instead, a pass play, a brilliant read from the Patriots’ Malcolm Butler and an interception that some call the greatest play in NFL history and some call the worst.

Read more on the NBA:

Box scoreWarriors 124, Cavaliers 114 (OT) | NBA Finals schedule

J.R. Smith’s greatest hits: Was NBA Finals Game 1 his magnum oop-us?

Cavaliers’ Tyronn Lue says anxiety caused him to step away

The NBA champion Bullets were the toast of D.C. 40 years ago, if only for a short time

Cavs-Warriors is the ‘Fast and the Furious’ of the NBA. That’s a good thing.