Among the monks, there was a certain Ichirai, a man of great strength and agility, who served the holy teacher Keishū at the Jōenbō. Having followed Jōmyō and fought in his wake, this Ichirai now wished to pass him, but found the beam too narrow. "Your pardon, Jōmyō," he said. He put his hand on the flap of Jōmyō's helmet, made a brisk leap over his shoulder, and went on fighting.
The Tale of the Heike, chapter 4, part 11 (translation by Helen Craig McCullough.)
Source.