Nick Kyrgios had one match point but it was Roger Federer who ultimately prevailed 4-6 7-6 (8-6) 11-9 to clinch the inaugural Laver Cup for Europe.
In an intense match in Prague, Kyrgios often had Federer on the ropes but just couldn't get over the line as the Swiss star secured the victory, leaving the 22-year-old Canberran in tears.
If Kyrgios had been able to win, it would have tied the scores between the world and European teams and forced a final doubles match.
"It was tough", Kyrgios said of the loss.
"When I'm playing for myself, sometimes I don't put the greatest effort in. When I play with these guys I'm playing for something as a team.
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"I'm playing for the whole team. It's the same in Davis Cup. I'm playing for the country, playing for the guys on the bench.
"I know that every single one of these guys up here has put effort into this week, whether that's practice or supporting other guys.
"We all bought in as a team. That's why it hurt. I gave everything I had. I came up short, and I knew that we were going to be favourites going to the doubles. That was in the back of my mind."
After the pre-match warm-up, the Australian - who usually crouches at the net before the first game - took a knee.
It sparked speculation he was showing solidarity with more than 100 American NFL players, who themselves knelt during the playing of their national anthem before matches on Sunday.
They were protesting against comments by US President Donald Trump, who on Saturday said that those who failed to stand for the anthem should be fired by NFL teams.
Kyrgios though rebuffed the claims in the post-match press conference.
"F**k no. Serious?" The Australian responded to the question from journalists.
"I'm doing that before most matches just to remember, you know, the two most important people that have passed away."
Kyrgios got the only break of serve in the first set but soon found himself a break down at the beginning of the second.
But after a medical time out, the Australian broke back and took it to a tiebreak.
He saved three set points in the breaker but 19-time grand slam champion Federer eventually levelled things up.
The match then went to a champions tiebreak which Kyrgios led 6-2 at one point.
But Federer battled back and Team Europe got the point needed for victory when Kyrgios sent a forehand into the net.
"It has been such an amazing and fun week and I'm so pleased the event has worked as it has," Federer said post-match.
The world team had clawed their way back into the tournament on Sunday with a win in the doubles match, while John Isner beat Rafael Nadal 7-5 7-6 (7-1).
