This opens a three-week window of time for the Patriots to activate him from injured reserve and add him to their 53-man roster.
Keene, 21, was selected with the No. 101 overall pick in the third round after the Patriots traded up to get him.
Keene signed a four-year, $4,057,645 rookie contract including a $832,294 signing bonus.
In 2020, Keene has appeared in one game and caught one pass for eight yards receiving.
During his three-year college career, Keene recorded 59 receptions for 748 yards receiving (12.7 YPC) and eight touchdowns, to go along with 11 rushing attempts for 33 yards (3.0 YPC) and no touchdowns.