With half time rapidly approaching at the Citrus Bowl, Tony Pulis's men looked poised to bring a slender advantage into the break.
However, Brazilian legend Kaka had other ideas, marching through Albion's defence before placing the ball beyond the reach of Myhill via the post to level matters in timely fashion.
Within four minutes of the restart, Carlos Rivas flipped the game on its head by powering a 25-yard free kick past Myhill to stun the visiting Baggies.
West Brom came close to getting back into the game when James Morrison latched on to a loose ball on the edge of the box, but his volley went just over the bar.
Orlando sealed their victory in the 86th minute when Pedro Riberio threaded a pass through the Baggies' defence and Rochez slotted the ball past Myhill into the net.