11:15 AM -- Travis expressed his disappointment over not being able to jet to L.A. for the awards show ... saying on "The Pat McAfee Show" he wishes he could go and "watch her win every single award that she's nominated for" -- but his day job simply won't allow it.

Just like we reported, Travis explained he will be traveling to Sin City on Sunday -- the same day of the Grammys -- and while he'll be supporting in spirit, he'll have to be with the team as they focus on bringing a Lombardi Trophy back to Kansas City.

Taylor Swift's been showing up to her boo Travis Kelce's games to cheer him on ... but he won't be returning the favor during her big night at the Grammys -- but for good reason.

Sources with direct knowledge tell TMZ ... the Kansas City Chiefs tight end will actually be arriving in Vegas the same weekend as music's biggest night ... where he and the team will be on a strict schedule ahead of squaring up to the 49ers for the Super Bowl.

This kills any hope from Swifties that TK would show up as Taylor's plus-one at the Grammys -- as they all realized his spot in the SB meant he'd no longer play in the Pro Bowl the same day ... and would therefore technically be free to hit up the Grammys with Tay Tay.

Alas, it ain't gonna happen -- our sources say there's no chance Travis shows up in L.A. this weekend. So, it looks like Taylor's gotta find company elsewhere or even ride solo for the glam evening this weekend. ... where she's up for 6 awards.

Of course, the conflict in their schedule doesn't signal any trouble in paradise between the pair ... remember, he just dropped the L-bomb after the Chiefs earned their way to the Super Bowl following a 17-10 win over the Baltimore Ravens. AKA, they're doing just fine.

While TK's been soaking up Taylor's PDA-packed show of support lately, many NFL'ers haven't ... blasting the singer for making the games about her -- even though she has no control over the stadium cameras ... something both he and she have made abundantly clear.

For his part, Travis is totally aware of the venom directed at his woman ... telling off-field reporters days ahead of the AFC Championship Game they frequently discuss blocking out all of the "outside noise."

Fortunately for him, he won't have to hear any of it on a huge showbiz stage -- his mind's strictly focused on football right now ... and his GF's more than capable of handling her business in the spotlight.