The person spoke on condition of anonymity because the announcement has not yet been made. The NBA is scheduled to announce the winner Monday.
The No. 1 overall pick from Kentucky posted the best rookie season by a big man since Tim Duncan. He averaged 18.1 points, 10.7 rebounds and 1.7 blocks and helped the Timberwolves win 13 more games than they did the previous season. Towns played all 82 games and was named Western Conference rookie of the month in all six months the award was handed out.
From the night of the NBA draft all the way to the end of his first season, Towns stood head and shoulders above the rest of his rookie class.
Towns turned 20 early in the season but showed the polish and poise of a veteran from the very early stages. His ability to pass, rebound, block shots and score from the paint and 3-point line make him the quintessential big man for the modern era and give the Timberwolves hope that they have finally found the star players needed to carry them out of the abyss.
"He's going to be a Hall of Famer in this league," Oklahoma City star Kevin Durant said.
Towns is the second straight Timberwolves player to win the rookie of the year award, after teammate Andrew Wiggins had a similarly convincing debut. Add to those two young stars a promising supporting cast including Zach LaVine, Ricky Rubio, Gorgui Dieng and Shabazz Muhammad that will be coached next season by Tom Thibodeau, and the Wolves believe they have the ingredients to finally end a 12-season playoff drought.
It didn't take Towns very long to make an impact. He had 28 points and 14 rebounds in the second game of the season, a victory over Denver, and though many rookies hit a wall in the middle of the long, grueling NBA regular season, Towns got better as the season went on. He averaged 21.3 points on 55 percent shooting and 11.7 rebounds in the final 31 games of the season.
Towns routinely greeted questions about his success with a shrug. The Timberwolves still won only 29 games and finished far out of the playoff picture in the Western Conference.
"People who know me know I'm never satisfied. I've never felt like I've had a good game," Towns said near the end of the season. "It's hard to get me to even say I played good. That's just in me. I'm just never satisfied. A lot of my friends get annoyed by it. I'm never happy about anything, playing-wise. I always think there's things I messed up on, things I should've done differently that could've A) made us win or B) made the win easier."
Towns would occasionally find one of his rookie of the month awards buried in his locker while he was looking for a pair of socks after a game.
"He's about winning," Towns' father, Karl, said. "He's not about no accolades. Karl doesn't take losing. He's never going to settle. That's the drive in him. That's what drives Karl. He has goals that he's set, and he's not going to be happy until he achieves them."