 As such, he gained the household's trust and was permitted on the premises.On that day, Mercader asked Trotsky to look over something he had written, and as Trotsky read the work, Mercader removed an alpine climbing axe from his coat and struck Trotsky in the back of the skull.The blow to Trotsky's head was bungled and failed to kill Trotsky instantly, as Mercader had intended.