The Memphis Grizzlies have agreed to a four-year, $105 million contract extension with Jaren Jackson Jr., locking up a core player ahead of a Monday deadline.

Jackson's agent Austin Brown confirmed the news to ESPN's Adrian Wojnarowski. Jackson was expected to sign the extension prior to Monday's 6 p.m. ET deadline for 2018 draft class players to do so.

The Grizzlies selected Jackson as the No. 4 pick in 2018 out of Michigan State. A versatile, 6-11 forward, Jackson, 22, earned All-Rookie honors in 2019. He anchors Memphis' young core alongside point guard Ja Morant.

Jackson's an effective scorer, defender and 3-point shooter who's averaged 15.4 points, 4.7 rebounds, 1.6 blocks and 1.1 steals while shooting 48% from the field and 37.4% from 3-point distance on 4.5 attempts per game in three NBA seasons.

Jackson missed all but 11 games last season with a meniscus tear in his left knee. He was expected to miss the entire season, but returned for the Grizzlies' late playoff push that resulted in the No. 8 seed in the Western Conference. He was active in preseason Grizzlies games and is healthy heading into Wednesday's season opener against the Cleveland Cavaliers.