CC Madhya 13.189

tabe mahāprabhu ratha pradakṣiṇa kariyā
ratha-pāche yāi’ ṭhele rathe māthā diyā
Word for word: 
tabe — at that time; mahāprabhu — Śrī Caitanya Mahāprabhu; ratha — the car; pradakṣiṇa — circumambulation; kariyā — doing; ratha-pāche — to the rear of the car; yāi’ — going; ṭhele — pushes; rathe — on the car; māthā diyā — by placing the head.
Translation: 
After circumambulating Jagannātha, Śrī Caitanya Mahāprabhu went behind the car and began pushing it with His head.