EXCLUSIVE

The competition on the 'Amazing Race' and "Big Brother" mash-up is gonna be fierce, because it's stocked with a lot of previous winners and fan favorites hauling ass around the world.

Sources tell us James Huling, who won America's Favorite Houseguest on season 17 of "Big Brother," will be partnering with Corey Brooks, who appeared on season 18. James also appeared on season 18, but didn't win.

As we previously reported ... "Big Brother" alums Caleb Reynolds and Rachel Reilly are also in the race. Rachel won season 13 of 'BB' and Caleb's got experience from being on two seasons of "Survivor" too.