The popularity of New Orleans Pelicans rookie Zion Williamson continues to skyrocket -- both on and off the court.

NBA Auctions launched a bid for one of his game-worn Pelicans City Edition uniforms on Feb. 27. As of Tuesday afternoon, it remains one of the most popular items on the site -- cracking over $15,000 with the close date set for March 19.

More memorabilia products for Williamson have been sold since his NBA debut Jan. 22 than any other player across the Fanatics network (which includes NBAStore.com), according to the company. And for merchandise and memorabilia sales combined, he has been a top-five-selling NBA player, with a 175% spike in sales month over month.

Fanatics wouldn't release specific figures to ESPN.

"We've seen incredible demand for both his Duke Blue Devils and New Orleans Pelicans products from fans around the world," Fanatics Authentic executive vice president Victor Shaffer said.

In January, when the NBA and National Basketball Players Association released the league's most popular jersey and team merchandise lists for the second consecutive year, Williamson ranked 15th despite not having played a single game in that period (results were based on NBAStore.com sales from October 2019 through December 2019, during which Williamson was rehabbing a knee injury).

His laundry list of endorsements also include Jordan Brand, Gatorade, NBA 2K, Panini America and Mountain Dew.

"I've always knew that memorabilia was a big part of the game because everybody wants an autographed jersey, signed basketball or just kind of anything to do with game-worn gear," Williamson told ESPN, while confirming his new multiyear partnership with Fanatics as his exclusive memorabilia distributor.

"It was just me, I've just never kind of asked for any of that [growing up]," he added. "Maybe it was my competitive spirit that made me not want to ask, but now that I'm officially in it, it does open my eyes to another level of the money people spend on it or the time and effort that people truly take to get a card or to get a basketball and it's impressive."

On Tuesday, Williamson was named Western Conference Rookie of the Month for February after averaging 25.7 points, 6.2 rebounds and 2.6 assists in 9 games. The 19-year-old faced LeBron James and the Los Angeles Lakers twice in the month, and despite losing both times, he described James as "thinking plays ahead while everybody else was probably thinking about the play going on."

"He really got his teammates involved, he got to his spots and he showed why he is who he is," Williamson said of James.

Following Sunday's game against Los Angeles, Williamson was also spotted gifting Lakers center JaVale McGee with his game-worn jersey and a hug before walking away empty-handed.

Despite the recent Fanatics memorabilia deal, Williamson admits he didn't grow up asking for autographs, but he has now grown to appreciate the value of highly sought-after items, such as his jerseys.

"I don't think it takes away from the competitive aspect at all because that's done after the game," Williamson said of jersey swaps among current players. "I've swapped jerseys with a few players like PJ Dozier, Ja Morant, Khris Middleton. I swapped with them because they're all from South Carolina and you just have a different connection with different people, so I don't see nothing wrong with it as long as you're battling when it's game time, that's all that matters."

The business of Williamson's sports merchandise has begun to blossom so much that it's taken him a while to perfect his autograph style. Since his junior year of high school, he has switched it up multiple times before currently settling on putting his last name first then going back to sign his first name to provide a cleaner look.

He plans to keep a few items from his rookie year, but his most cherished item has nothing to do with the NBA.

"I don't think it's anything big to the world, but it's big to me. My freshman year of high school, we had a field day where it was Freshmen vs. Sophomores, Sophomores vs. Juniors and all that good stuff," Williamson said. "So, each grade had their own color shirt, and I had my whole class, every kid, a big class of 45 people, sign my shirt, and I still have that shirt. It's something I hold on to. It sits in my drawer somewhere."