During the summer, the NBA announced major changes to the replay system, with the implementation of a coach's challenge system. It didn't take long for the new wrinkle to come into play, as Toronto Raptors coach Nick Nurse made history by calling for the first regular season challenge that the NBA has ever seen just a few minutes into his team's opening night game against the New Orleans Pelicans. 

With just under three minutes left in the first quarter, Norman Powell made a strong move to the basket, but unfortunately for him he used a little too much force. His elbow crashed into Josh Hart's face, and the refs called an offensive foul. It seemed like a pretty straightforward call, but Nurse disagreed, and immediately called for the challenge. 

After a brief review, the refs upheld the call, which wasn't a surprise at all. 

Along with fouls, coaches can challenge a variety of plays, including out of bounds and basket interference calls. But whereas those are pretty straightforward, foul calls are far more subjective, which could make some of these reviews interesting. 

That wasn't the case on this call, however, which meant the review thankfully didn't take very long. Still, it completely disrupted the flow of the game, which could get obnoxious as the season moves forward. These games are already too long, and challenges will only add another couple of stoppages to the game. 

The good news in that regard is that coaches get just one challenge per game, regardless of whether or not the call gets overturned. It was an interesting decision for Nurse to use his so early, as timing will be an interesting dilemma for coaches. If they try to save it for a big moment late in the game, they may end up wasting it. Nurse opted for the early use, which could be wise if there's an obvious error to overturn, but that wasn't the case here. 

Even though he ended up misusing his challenge in this game, Nurse still made history and opened up a new era of replay review in the NBA.