Patroclus though – the spear in his grip was shattered,
the whole of its rugged bronze-shod shadow-casting length
and his shield with straps and tassels dropped from his shoulders,
flung down on the ground – and lord Apollo the son of Zeus
wrenched his breastplate off. Disaster seized him –
his fine legs buckling –
he stood there, senseless.

– Homer

The Iliad, Book 16, lines 930-935. When Patroclus disobeys Achilles’s instructions to pursue Hector and his men all the way to the walls of Troy and kill many Trojans in a series of charges, the god Apollo enters the battle as an ally of Hector. He sneaks up behind Patroclus and hits him so hard on the back that his helmet flies off, his spear is shattered, his shield drops from his shoulders, and his breastplate is torn off by Apollo. Apollo’s intervention will enable Hector to kill Patroclus.