Matic established himself as a key player during his time at Stamford Bridge and was part of the side that won the Premier League title last season.
However, the Serbian was susprisingly sold to domestic rivals Manchester United in the summer for £40m and speaking ahead of the game, Conte only had good things to say about the former Benfica man admitting that it is "unfortunate" that he is no longer playing for the club.
"About this player I can talk only really well because he played with us last season," the Italian told the press.
"I think he was one of the key players in winning the title.
"Now Matic, unfortunately, is playing for Manchester United. I wish for him the best. Not on Sunday, but in the future."
Naturally Conte was then pressed on why such an important player was allowed to join a direct rival, a question that he wasn't prepared to answer.
"In the past we have already managed this topic," he replied.
"I don't want to come back and speak about the past because I think it's not important, not interesting for us."