Andy Murray says the build-up to his all-British China Open quarter-final against Kyle Edmund will be "uncomfortable" for him.
The world number two is a Davis Cup team-mate of Edmund, 21, and regularly trains alongside him during off-season.
The Scot, 29, beat Russia's Andrey Kuznetsov in straight sets on Wednesday to go through while Edmund beat Spaniard Roberto Bautista Agut.
Their match is expected on court in Beijing at approximately 08:45 BST.
"It's always a little bit uncomfortable because, normally, when you see your friends and stuff in the locker room you have a chat, joke around," said Murray.