CC Madhya 9.48

yadyapi asambhāṣya bauddha ayukta dekhite
tathāpi balilā prabhu garva khaṇḍāite
Word for word: 
yadyapi — although; asambhāṣya — not fit for discussion; bauddha — followers of Buddha’s philosophy; ayukta — not fit; dekhite — to see; tathāpi — still; balilā — spoke; prabhu — Lord Śrī Caitanya Mahāprabhu; garva — pride; khaṇḍāite — to diminish.
Translation: 
Although the Buddhists are unfit for discussion and should not be seen by Vaiṣṇavas, Caitanya Mahāprabhu spoke to them just to decrease their false pride.