For the first time in NBA history, coaches are allowed to challenge one call per game.
And late in the first half of Golden State's preseason win over the Timberwolves on Thursday, Steve Kerr "threw the challenge flag."
The officials ruled the ball went out of bounds off the Warriors. But upon review, it really was off Minnesota forward Robert Covington.
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"I don't like the rule," Kerr told reporters when asked about the process of challenging. "I don't like replay at all. I think replay should be limited to the buzzer beater at the end of every quarter.
"They sent us the rules and we watched the video tape, so it seemed like something we might as well try. You have to call a timeout in order to challenge.
"It seems like what you have to do is make sure you're not wasting a timeout on a play that's not worth challenging. So that's gonna be a big factor.
"If it's your timeout coming up, or if there's a mandatory coming up that's yours, or if you're on the bad end of a run and you see something that's questionable, you might as well take the timeout and review it. That way there's no harm done if you don't get the call."
Steph Curry -- who dropped 40 points and six assists in just 25 minutes of action -- had a funny reaction when the referees overturned the call and gave the Dubs possession:
Like his head coach, the two-time NBA MVP doesn't seem to be a big fan of the new rule.
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Golden State Warriors
“It’s interesting," Curry said to the media. "There’s obviously a flow to the game. You don’t want to get in the way of that. It’s an option that they (coaches) have and they gotta be selective about it.
"He (Kerr) won it tonight, but hopefully he doesn’t get too crazy, too challenge flag happy with it. It's a useful tool if you get it right. If you don't, it kinda looks bad because it stops the game and everybody's kinda looking at you like, 'What were you thinking?'
"You gotta be a little vulnerable in that situation."