The other side: NBA official. 

After attending several officiating meetings since the start of NBA Summer League on Thursday, the former Arizona Wildcat and longtime NBA veteran made his reffing debut, donning No. 77 on the back of his gray uniform. 

"Let me say this: First of all, part of the reason why I agreed to do it was because I have a tremendous amount of respect for the officials," Jefferson said. "I understand how important they are to our game. ... For me to get the opportunity and come out here, run around a little bit, it's intense. Anyone who wants to criticize an official, just referee a high school game first, then you might look at a little differently." 

Jefferson's first call was a loose ball that bounced out of bounds. Jefferson blew his whistle and signaled that the ball was last touched by the Trail Blazers, which drew praise from Knicks fans, except the call was overturned by other officials.  

"Apparently, upon review, I was correct. But that's part of learning how to be a referee; being confident in your calls and being demonstrative," Jefferson said. "I was like, 'Oh, that's the right call, then there was all his hoopla and everyone arguing, which is going to happen, but I'm waiting to see the review.

"I gotta go do my study like all these other referees after every single game, every single call — they go look at all the information to make sure they get better. That's going to the be the first one we look at to see if that was right. ... What I learned in these five or six days, going to class and getting to know them — it's really about their mindset.

"Like I said, I might've had the call right, but I wasn't demonstrative, I wasn't confident with it. ... They teach these men and women how to be intense, how to be locked in on the moment, all these little things. There's so many intricacies you guys wouldn't even believe."  

The official referee statistics for Jefferson, who is now an ESPN commentator, in a 10-minute quarter: Two whistles blown, one overturned call, one over-the-back offensive foul (which generated loud cheers from Knicks fans) and six passes to free-throw shooters. 

Despite having favorable calls for the Knicks, Jefferson was heckled. When the former New Jersey Nets star first stepped on the court, one Knicks fan could be heard yelling, "R.J., you suck!"

"I have no issue with the Knicks fans. When they see my face, I understand they get frustrated for all the years of pain we tormented them with. ... I respect the Knicks. Part of the rivalry, it's Ohio State-Michigan, UCLA-USC, Duke-North Carolina," Jefferson said. "The Knicks are the team of the town. We're the Nets, so there's always going to be that rivalry and there's always going to be that energy, and I have no problem leaning into it, playing into it.

"It's nothing but a ton of of respect in the Knick organization. ... Most refs aren't being heckled by name, but this was one of those times. Normally, I'm used to being able to say stuff back, so that was the hardest part."

While installing Jefferson as a temporary referee may seem like a gimmick from the NBA, it served as a sentimental moment for the one-time champion who played in the league for 17 seasons since he was a first-round pick in 2001. 

"The craziest thing for me: I haven't been on an NBA court since I retired," he said. "Putting on this jersey or putting on a basketball jersey, once you're involved in the NBA and you get to participate in game action, that's a once in a lifetime experience, and I don't any of that for granted.

"Like I said, I haven't been on an NBA court since I retired since I retired, so this? Man, I was like a kid in the candy store when I started running up and down."