They've never met before so the H2H is 0-0.
http://www.atpworldtour.com/Players/Head-To-Head.aspx?pId=MC10&oId=D875
The 20yr old Bulgarian turned pro 3 years after Andy but so far has no ATP titles. Career win/loss is 30/20 (Andy 308/105). He was the world #3 junior in 2008 and that year won both the Junior Wimbledon and USO titles.
A very winnable match for Andy but the younger man could make it a tough one.