His best years came while teamed with quarterback Dan Marino and head coach Don Shula.[3]
Jensen wore jersey no. 11 because he entered the league as a quarterback, then an ineligible number for a wide receiver. After Marino was selected in the 1983 NFL draft, it became evident that Jensen would need to find another way to survive on the Dolphins roster. He became a human Swiss army knife, with a knack for making tackles on punt and kickoff coverages and converting third down opportunities as a running back or wide receiver in the offensive set with Marino. On Mexican TV he was known as "the Thousand Uses" ("el Mil Usos" in Spanish) due to his versatility.
His best season statistically was in 1989 with 61 receptions for 557 yards and 6 receiving touchdowns, with 8 rushing attempts for 50 yards, and 1 passing attempt and completion for a 19-yard touchdown.[4] He was named the Dolphins special teams most valuable player in 1988. Jensen finished his 12 NFL seasons with 229 receptions for 2,171 yards and 19 touchdowns. He also passed for two touchdowns. In 1989, he caught Marino's 200th career touchdown pass. Jim was also the 1988 NFL Special Teams Player of the Year.[citation needed]