Organizers announced the selection Friday morning, three days after they revealed the first batch of films, including the closing night selection, Alan Rickman's A Little Chaos.
It's not clear what caused the delay, but it is unusual that a previously announced gala film would then be revealed as the opener.
TIFF's director and CEO Piers Handling said he is thrilled to have David Dobkin's The Judge kick off the event:
"Dobkin has delivered a moving, textured story about family, duty and the way we remember our past. We couldn’t have asked for a better start."
The family drama stars Robert Downey Jr. as a big city lawyer who returns to his childhood home where his estranged father (Duvall), the town’s judge, is suspected of murder.
Other stars with films in this year's festival include Jennifer Aniston, Andrew Garfield, Kevin Costner, Octavia Spencer, Denzel Washington, Anthony Michael Hall, Steve Carell, Tina Fey, Vanessa Redgrave, Channing Tatum, Mark Ruffalo, Jason Bateman, Julianne Moore and Benedict Cumberbatch.
The 2014 Toronto International Film Festival runs Sept. 4 to 14.