Telling these two apart

I have problems differentiating between the mangrove pitta, the only local pitta left in Singapore, and the blue-winged pitta, a migrant.

Mangrove pitta (left) Blue-winged pitta (right)

I did some research and thought it would be nice to share it with everyone.  Both species are placed side-by-side for easier comparison. Three distinguishing areas to look for: -

1. Mangrove pitta has less blue on the wing
2. Mangrove has a longer beak
3. Mangrove's head patch extends further back and is larger

Personally, the head patch is probably the easiest way to tell them apart in the field.