CC Antya 4.106

ratha-agre prabhu taiche karilā nartana
dekhi camatkāra haila sanātanera mana
Synonyms: 
ratha-agre — in front of the car; prabhu — Śrī Caitanya Mahāprabhu; taiche — similarly; karilā nartana — performed dancing; dekhi — seeing; camatkāra haila — was astonished; sanātanera mana — the mind of Sanātana.
Translation: 
During the Ratha-yātrā festival, Śrī Caitanya Mahāprabhu again danced before the car of Jagannātha. When Sanātana Gosvāmī saw this, his mind was astonished.