What to do in times of data inconsistency in Master-Master Replication in MySQL?

I am building an architechture consisting MySQL Master-Master replication with HAProxy in its front. For HAProxy i am using round_robin algorithm to distribute loads between two masters. My question is when there is a heavy write situation as Seconds_Behind_Master will be greater than 0, what should I do for the data inconsistency will arise when HAProxy will go divert to an unupdated Master?