Shortstop J.P. Crawford, the Phillies' top position player prospect, suffered a "very slight tear" of the ligament in his left thumb and will miss the remainder of the Arizona Fall League season, said Joe Jordan, the team's director of player development.

Crawford suffered the injury while making a tag play in a game last week. No surgery is required and Jordan said Crawford would be 100 percent healthy before spring training.

"It's a very, very slight tear in the UCL ligament in his left thumb," Jordan said. "It's so slight they had to read the MRI three times to find it. Surgery is not necessary but he is in a splint and will be immobilized for three to four weeks so his AFL season is over."

Phillies second baseman Cesar Hernandez also suffered a torn UCL in his left thumb late in the big-league season. His injury was more severe and required surgery. Hernandez is also expected to be 100 percent healthy by spring training.

Crawford, 20, was the Phillies' first-round draft pick in 2013. He missed the first month of the 2015 season recovering from an oblique strain suffered in spring training. He appeared in 107 games between Single A Clearwater and Double A Reading, batting .288 with six home runs, 42 RBIs and 12 stolen bases.

Crawford had been playing for the Glendale Desert Dogs in the Arizona Fall League. He had just three hits in 20 at-bats with two walks and three runs scored in five games for the club.