Harvey Mason Jr. -- interim President and CEO of the Academy -- says, "We understand that The Weeknd is disappointed at not being nominated. I was surprised and can empathize with what he’s feeling. His music this year was excellent."

He adds, the Grammys had no issue with him performing at the Super Bowl and would have loved to have him also perform for the awards show. TMZ broke the story ... negotiations for The Weeknd's Grammy performance got nasty, and our sources say he was issued an ultimatum -- play for us or the Super Bowl.

As for Weeknd receiving zero nominations -- Mason claims there was nothing nefarious to it. He says, "To be clear, voting in all categories ended well before The Weeknd’s performance at the Super Bowl was announced, so in no way could it have affected the nomination process."

As we reported ... it was revealed The Weeknd would be doing the SB Halftime Show on Nov. 12. The Grammys point out its voting deadline for noms was in October. Mason is adamant nobody was upset about the prospect of the singer performing at both events ... because the Grammys happens first.

Mason also says he's "saddened" over The Weeknd and his team saying "The Grammys remain corrupt." He says ... "I try to empathize with where that came from, but it was difficult to hear."

Despite the apparent damage control, it appears this controversy's not going away anytime soon. The Weeknd's manager, Sal Slaiby, also slammed "corrupt leaders" at the Grammys and demanded transparency.