SALT LAKE CITY -- The Utah Jazz signed a 5-year-old, free-agent guard to a one-day contract for a special scrimmage Monday night.

JP Gibson, who was diagnosed with acute lymphoblastic leukemia, signed his contract with Jazz president Randy Rigby before joining the team in uniform for the annual preseason intrasquad scrimmage at EnergySolutions Arena.

JP was joined by his parents, Josh and Megan, and his 2-year-old sister, Elsie. The family was hosted by the Jazz and photographer Jon Diaz's "Anything Can Be" project, which creates storybooks for children with cancer about their dreams and wishes.

JP, wearing a No. 1 jersey, even got to play in the scrimmage. He was passed the ball and dribbled into the lane, where center Rudy Gobert lifted him up so he could dunk and slap hands with some players as fans roared.

The Jazz tweeted a photo of JP holding up his new Jazz jersey with his family.

Welcome to the Jazz, JP! pic.twitter.com/kI36etzAK2 — Utah Jazz (@utahjazz) October 6, 2014

"JP loves most sports, but basketball is definitely his favorite," Megan Gibson said in a statement released by the Jazz. "When he was just over a year old, he would sit with my husband, Josh, watching games. He started insisting on shooting hoops for an hour each night before bedtime when he was just 15 months old. He knows he has to be 6 before he can play Junior Jazz, and he reminds us all the time that he can't wait until he's 6."

The Associated Press contributed to this report.