'Modern Family' Star -- Might Have to Miss Oregon Game ... If Work Calls

"Modern Family" star Ty Burrell has proof that a $170k-a-week job can have drawbacks ... with the Oregon Ducks superfan saying he might have to miss the National Championship -- if work calls.

As we previously reported, Burrell is a hardcore Ducks supporter and personal friends with the head coach -- and publicly declared he'd be at the game in Texas to cheer on UO against Ohio St.

There's just one thing that can stand in his way ... "Modern Family" ... and when we got Burrell in L.A. on Monday, he admitted if push comes to shove ... it's a fight he knows he can't win.