Dallas Mavericks forward Cooper Flagg has taken over the NBA's Rookie Ladder. While Flagg had a slow start to his career, he's performed well lately. In 24 games, he's averaged 17.3 points, 6.3 rebounds and 3.3 assists. However, not everyone agrees that the former Duke star should be considered for the top place. One of the people who had something to say about the latest rookie ladder was Ron Harper, father of San Antonio Spurs rookie Dylan Harper. On X (formerly Twitter), Harper took a dig at the Mavericks player. He brought up the team's rocky start to the 2025-26 NBA season. The Mavericks are 9-16 in the year, as things haven't been productive for the team. They've dealt with injuries to their roster, which has affected their standing. "So we will credit losing on bad teams now? lol," Harper commented.Compared to the Spurs, the Mavericks' season hasn't been positive. San Antonio is 17-7 this year and beat the LA Lakers on Wednesday at the quarter-finals of the Emirates NBA Cup. They have a shot at potentially competing for the $500,000 prize of the In-Season Tournament. Even with a slow start to the season, Cooper Flagg has become more comfortable in the league. In the last five games, he's averaged 23.2 points, 5.8 rebounds and 2.2 assists. During that stretch, he led the Mavericks to a 4-1 record. Harper, meanwhile, has begun to progressively contribute to the Spurs. He has appeared in 14 games, averaging 13.4 ppg, 3.1 rpg and 3.9 apg. Cooper Flagg reacts to being compared to other all-time greatsAlthough it's Cooper Flagg's first year in the NBA, experts cannot help but compare him to other great players. He has been compared to the likes of Michael Jordan, LeBron James and Kobe Bryant. Recently, Flagg was asked about his thoughts on having his name next to some of the best basketball stars. “It’s incredible,” Flagg said. “It makes me feel really blessed to be in this position and for everything to happen the way it did, coming here at this point in my life. I would have never imagined any of this when I was younger. It’s just a dream come true. I just feel so blessed and grateful to be here and be surrounded by great people.”The Maine native has shown brilliance on the court. He just needs more time to get the hang of things and become the Mavericks' leader. Coach Jason Kidd said Cooper Flagg has lived up to the hype of being the No. 1 pick. Most players selected first have a lot on their plates. But the 6-foot-9 forward has figured things out.