Drake -- Bails on Grammy Nomination Concert

Drake has pulled himself out of tomorrow's big Grammy Nominations Concert in L.A., TMZ has learned ... and it's all because the guy claims he's got a last minute "scheduling conflict."

The show had been promoting the rapper as one of their big acts since October ... but a rep for Drake tells TMZ something came up, and now he won't be able to attend.

"Unfortunately, due to scheduling complications, Drake will no longer be performing ... [he's] currently in the middle of his nationwide 'Would You Like A Tour?' and sincerely apologizes to his fans that he can’t be there."

According Drake's website, he's not scheduled to perform anywhere on Dec. 6th ... though he does have a show the following day in Missouri.

So, why the sudden conflict? We asked the rep ... but didn't get an explanation.