Canada's Vasek Pospisil played superbly to beat Dan Evans and level the Davis Cup first-round tie against Great Britain at 2-2 - forcing a deciding fifth rubber in Ottawa.
Pospisil, ranked 133rd, beat world number 45 Evans 7-6 (7-3) 6-4 3-6 7-6 (7-5) in the fourth match of the tie.
The outcome will now be decided by the final match between Kyle Edmund and Canada's 17-year-old Denis Shapovalov.
The winners of the tie will travel to France for a quarter-final in April.
Both Britain and Canada are without their leading players in Ottawa, as world number one Andy Murray recuperates after the Australian Open and number four Milos Raonic is injured.