Team USA produced a clean sweep to record their first-ever victory in the history of the competition.
The positive test has put Shapovalov's chances of playing at the ATP Cup in doubt.
Denis Shapovalov edged out Rafael Nadal to take third place at the Mubadala World Tennis Championships.
Denis Shapovalov reached the semi-finals in Abu Dhabi after a dominant display over Taylor Fritz.
Bianca Andreescu will miss the start of the season in Australia after a tough 2021 season.
The 2019 runners-up finish bottom of Group B after failing to win all six matches they played across two ties.
Elias and Mikeal Ymer secured the win for the Swedes over the Canadians on day one of the event.
The Canadian will look to lead his team one step further after reaching the final in Madrid back in 2019.
Muguruza caps off what she describes as her 'best year' on the Tour by becoming the first Spanish woman to win the season-ending title.
The two tennis stars cited fatigue and injury as the reason why they have chosen not to play in the team event.
The American denied his Canadian opponent Denis Shapovalov the chance to defend his title.
Denis Shapovalov is on track to win his second consecutive Stockholm Open title after beating Felix Auger-Aliassime in the last four.
The Canadian reached the semis after beating the Dutchman in straight sets on Thursday.
There was a lot of emotion displayed during the second day of the season-ending event.
The Canadian was pushed to the limits by his Italian counterpart but managed to pull through.
Daria Kasatkina featured in Russia's 3-0 win over Canada in the Billie Jean King Cup today.
Canada are off to a winning start at the Billie Jean King Cup Finals.
Anett Kontaveit is a top 10 player and heading to the WTA Finals after claiming the title in Cluj.
Simona Halep will have the chance of winning a title on home soil after dismantling Marta Kostyuk in Cluj.
Anett Kontaveit is into back-to-back WTA Finals after another convincing win in Romania.