While Lemieux redshirted his freshman season, he did not miss a start between 2016 and 2019, starting 52 games over those four seasons.[4]
After his junior season, Lemieux and a group of teammates (including quarterback Justin Herbert) considered leaving for the NFL Draft, but collectively decided to stay.[5] Lemieux had also sought out an evaluation from the NFL's College Advisory Board and was advised to return to school.[6]
Lemieux was selected by the New York Giants in the fifth round with the 150th overall pick in the 2020 NFL draft.[10]
On Monday Night Football on November 2, he started his first game at left guard for Will Hernandez who tested positive for COVID-19. Lemieux retained the starting position for the remainder of the season, replacing Hernandez at left guard, playing in 12 games with 9 starts as a rookie allowing 25 pressures and five sacks.[11]
On September 16, 2021, Lemieux was placed on injured reserve after aggravating a knee injury in Week 1.[12] On September 22, Lemieux underwent season-ending surgery to repair his left knee's patella tendon. Lemieux was the 2nd Giants offensive lineman to be announced out for the season, following Nick Gates' injury in Week 2's Thursday Night Football.
On August 11, 2022, Lemieux injured his toe in week 1 of the preseason against the New England Patriots.[13] He was placed on injured reserve on August 31, 2022.[14] On November 19, he was activated from injured reserve.[15] On December 28, Lemieux was placed on season–ending injured reserve after aggravating his toe injury in Week 11 against the Detroit Lions.[16] He finished the season playing in 39 offensive snaps, Lemieux’s struggles continued, allowing five pressures and a sack.[17]
On October 19, 2023, the Giants placed Lemieux on injured reserve after tearing his biceps in practice.[18] He finished the season playing in 27 snaps and allowed just one pressure.
New Orleans Saints
On April 29, 2024, Lemieux signed with the New Orleans Saints.[19] He was released on August 27, and re-signed to the practice squad.[20][21] He was promoted to the active roster on September 25.[22]