Place chicken on a grill rack coated with cooking spray; grill 6 minutes on each side or until done. Cut into 1/2-inch-thick slices. Set aside.
Combine lettuce and next 5 ingredients (through onions) in a large bowl. Combine orange juice concentrate, vinegar, oil, salt, and black pepper; stir with a whisk. Pour juice mixture over lettuce mixture, tossing to coat. Divide lettuce mixture evenly among 4 plates; top evenly with chicken, oranges, and almonds.