John Fritz, Taylor Isner give Americans win over Canada at the ATP Cup

John Isner and Taylor Fritz beat their Canadian opponents on Sunday to give the United States a winning 2-0 lead in their ATP Cup match.

Isner beat Brayden Schnur 6-1 6-4 in 66 minutes to give the Americans the early lead. Schnur was a late replacement for Denis Shapovalov, who withdrew from the opening singles match on Sunday due to fatigue. The Canadian is recovering from having contracted COVID-19 at a recent tournament in the Middle East.

Fritz then came from a set down to beat No. 11-ranked Felix Auger-Aliassime 6-7 (6) 6-4 6-4 and clinch the match ahead of the doubles.

Isner saved the only break point he faced.

"I surprised myself with how well I played out here," Isner said in his on-court interview.

"You always work hard in the offseason, but you never really know what could happen in that first match of the year."

Isner broke twice in the first set and used his strong serve to capitalise on the advantage. The American hit 10 aces and won 46 per cent of his return points.

"I actually really like this court. It's not too fast, which I prefer. It gives me a little time to swing out on my shots being so big. That helps me out a lot," Isner said.

In the other day match on Sunday, defending champions Russia got off to a strong start when Roman Safiullin beat Arthur Rinderknech of France 2-6 7-5 6-3.

In night matches, Italy played Australia and Germany took on Britain.

On the opening day on Saturday, Argentina and Spain both cruised to 3-0 victories over Georgia and Chile, respectively. Serbia, despite playing without No 1 Novak Djokovic, beat Norway 2-1 and Poland took advantage of Stefanos Tsitsipas' injury-enforced absence in singles to beat Greece 2-1.

The 16 teams are dividing into four groups, with the winners of each group advancing to the semifinals on Jan. 7 and 8. The final is scheduled for January 9.