The NFL has reinstated Ravens rookie cornerback Asa Jackson following his four-game suspension without pay for violating the league's performance-enhancing drug policy.

The Ravens were given a roster exemption for Jackson through Jan. 14, so they don't have to make a transaction until then unless they want to activate the fifth-round draft pick now.

The suspension stemmed from unauthorized usage of Adderall, according to a source with knowledge of the situation.