Pierre Desir was a cornerback for the Tampa Bay Buccaneers who earned a 69.8 overall PFF defensive grade in the 2021 season, 29th among 120 qualified cornerbacks. His PFF coverage grade of 71.1 ranked 25th among 120 qualified cornerbacks. His run-defense grade of 53.2 ranked 84th at the position.
He recorded 2 interceptions on the season. Desir broke up 2 passes in coverage. He allowed a 79.0 passer rating when targeted by opposing quarterbacks. He surrendered 24 receptions in coverage. He also contributed 23 solo tackles in run support and open-field situations.