Sergio Estrada-USA TODAY Sports

The Boston Celtics have to be kicking themselves after a possible trade for reigning NBA Finals MVP Kawhi Leonard fell through last year.

According to ESPN’s Zach Lowe, Boston could have landed Leonard from the San Antonio Spurs prior to the 2018-19 season.

Unfortunately, general manager Danny Ainge refused to part ways with his two young stars.

“If there is a team feeling Leonard regret now, it is Boston,” Lowe reported. “The Celtics had the coveted young players and draft picks to outbid Toronto. Boston larded up its offer with draft picks, but declined to include Jayson Tatum or Jaylen Brown without gaining more assurance than was possible about Leonard’s health and interest in re-signing, sources said at the time of the trade.”

Ouch.

San Antonio ultimately traded Leonard and Danny Green to the Toronto Raptors for DeMar DeRozan, center Jakob Poeltl and a 2019 first-round pick.

The rest is history. Leonard averaged nearly 29 points per game en route to leading Toronto to an NBA Finals upset of the Golden State Warriors.

Meanwhile, Boston fell in the second round of the playoffs.

Heading into the offseason, the Celtics are at a crossroads. Kyrie Irving is slated to become a free agent and will likely bolt for the Brooklyn Nets.

Ainge and Co. are also hesitant to give up too much in a trade for Pelicans star Anthony Davis, primarily because of his status as a free agent following the 2019-20 season.