Dan Evans will play 17-year-old Denis Shapovalov in the opening rubber of Great Britain's Davis Cup first-round tie against Canada in Ottawa.
Friday's second singles rubber will be between Kyle Edmund and Vasek Pospisil.
Jamie Murray and Dom Inglot will contest Saturday's doubles rubber against Daniel Nestor and Pospisil.
Captain Leon Smith has confirmed world number one Andy Murray will not compete for Great Britain this weekend, saying it is the "right thing for him to do".
"We all miss Andy because he is such a great influence on the team both on and off the court," said Smith.