Rookies on Buffalo's offensive line ripped their shirts off and gave a heartfelt rendition of "I Want It That Way" as part of their introduction to the team on Thursday ... and honestly, we're impressed!!

Tanner Owen, Alec Anderson and the guys alternated the classic lyrics as superstars Josh Allen and Co. watched the performance ... with the QB even turning on his iPhone flashlight to replicate a lighter.

There was also a bit of dancing going on -- proving the guys were truly giving 100% out there, even if they didn't have an empty airport to use for the big performance.

Rooks have been showing off their pipes recently as part of the yearly tradition -- as we previously reported, Eagles top pick Jordan Davis wowed the crowd with his cover of "Mary Jane" by Rick James just a few days ago.