Murray made his comeback after an 11-month absence at Queen’s earlier this week, though any hopes of a deep run in a tournament he has won five times were ended when he was paired against Nick Kyrgios in the first round.
The Scot fared unexpectedly well against Kyrgios, but lost a gruelling three-set match in two hours 39 minutes.
He opted to head to the Nature Valley International in the hope of a run of matches, something that looked possible with a much weaker field than he had to contend with at Queen’s.
However, the draw was particularly unkind to him, handing him a first-round meeting with three-time grand slam champion Wawrinka.
If he gets through that tough test, British number one Kyle Edmund awaits in the second round.
Murray is yet to say whether he will play in Wimbledon, which starts a week on Monday.
Though still a tough draw, Wawrinka has not been without his injury problems and has failed to hit the heights following a double knee operation in 2017.
He reached the second round at Queen’s before losing to Sam Querrey.