Great Britain ended their Hopman Cup campaign with a 2-1 victory over the United States in Perth.
Katie Boulter and Cameron Norrie saw off 23-time grand slam champion Serena Williams and world number 39 Frances Tiafoe 2-1 thanks to a victory in the deciding mixed-doubles rubber.
Norrie, 90th in the rankings, earlier beat Tiafoe 7-6 (4) 6-0 but Williams levelled the contest by seeing off Boulter 6-1 7-6 (2).
In the decider, the American duo took the first set on a tie-break but Boulter and Norrie responded to win 3-4 (2) 4-3 (4) 4-1.
The British pairing finished their Group B campaign with two wins and a defeat but did not do enough to progress to the final.
The Americans finished bottom of the group after suffering three defeats, but Williams - who won all three of her singles matches - felt the preparation was key to her Australian Open hopes.
"It was perfect - it's just like this in Melbourne," she said, according to the Hopman Cup's website.
"It's the exact same sun and it gives me so many problems. After you serve, you are blind for the next two points.
"It was good to play three singles matches here, not to mention the mixed doubles."
