The Boston Celtics’ Jayson Tatum and the Utah Jazz’s Donovan Mitchell today were named the Kia NBA Eastern and Western Conference Rookies of the Month, respectively, for games played in December.

Tatum ranked second among Eastern Conference rookies in scoring (14.6 ppg) and fourth in rebounding (5.9 rpg) in 17 games in December for Boston, which went 11-6 to maintain its place atop the East standings.  He made a rookie-high 59 free throws and finished fourth or better among all first-year players in field goal percentage (52.9), three-point field goal percentage (45.1) and free throw percentage (81.9).  The 19-year-old forward scored in double figures 14 times, including two games with 20 points, and grabbed 10 rebounds three times.  Tatum recorded two of his three career double-doubles during the month.

Mitchell led all rookies in scoring (23.1 ppg) and steals (1.77 spg) in 13 games during December, and his 88.2 free throw percentage (45-of-51) was the highest mark among first-year players with more than 20 attempts.  He also ranked third among Western Conference rookies in field goal percentage (50.7) and fourth in assists (3.8 apg).  The 21-year-old guard opened the month by scoring 41 points in a 114-108 victory over the New Orleans Pelicans on Dec. 1, a Jazz rookie record and the first 40-point game by an NBA rookie since Blake Griffin in January 2011.  Mitchell scored more than 25 points seven times in December.