Louisville will be without its top returning pass rusher in 2019.

Defensive lineman Jonathan Greenard, who was expected to be a key piece in the Cardinals' defense next season after missing nearly all of 2018, announced Tuesday that he is transferring.

"These past 4 years have been filled with many memories that I will never forget. The many ups and downs came with multiple life lessons. I thank my family, my teammates and everyone who was involved throughout my journey at UofL. This was one of the hardest decisions I was faced with," he wrote on Twitter.

"I will always have Louisville in my heart. I thank you all for never giving up on me. I thank you all for the support and many wishes during this tough time in my career. I am forever grateful for the opportunity to play college football."

Greenard didn't play again in 2018 after suffering a wrist injury in the season-opening loss to Alabama.

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He had been rumored to be leaving the program since news broke of a possible transfer in December. Last week, he entered his name in the NCAA transfer portal, which signifies an interest in transferring.

A three-star recruit from Hiram, Georgia, Greenard played in 23 games for the Cardinals in four years. His biggest season was 2017, when he led the team in tackles for loss with 15.5 and was tied for the team lead with seven sacks.

He is the third Louisville player to transfer this month, joining running back Trey Smith and linebacker Kam Jones.

Justin Sayers: 502-582-4252; jsayers@courierjournal.com; Twitter: @_JustinSayers. Support strong local journalism by subscribing today: courier-journal.com/justins.