Chicago - John Isner, the tall American with the blistering serve, has added a new role in the last week. He's a dad.
His wife gave birth a week ago to their first child, a daughter, an experience Isner described as "the best moment of my life for sure."
Being separated this week while he competes in the Laver Cup has been difficult.
Isner said he received a picture on his phone of his daughter watching him play for the first time.
"I don't think she will remember it," he joked.
"My wife is changing her diaper and I'm on the TV."
He's going to skip upcoming tournaments in Asia to be a family man.
"It's been super tough being away right now," he said.
"I certainly miss my daughter incredibly much right now."
He's also hoping that his family will be able to travel with him next year.
"We'll see how that goes," he said. "It's going to be an adjustment."
Isner's career has been on the upswing at age 33. He won his first Masters 1000 title at Miami, beating Alexander Zverev in the finals. And later he reached the Wimbledon semifinals, losing a nearly seven-hour-long marathon to Kevin Anderson, who is his team-mate this week on Team World.
Isner had a difficult loss on Saturday in the Laver Cup, falling to Zverez, who rallied for a 3-6, 7-6, (10-7) victory.
Roger Federer then beat Nick Kyrgios 6-3, 6-2 to give Team Europe a 7-1 lead in the team competition at the United Centre.
But in the night session, Anderson downed Wimbledon and US Open champion Novak Djokovic 7-6, 5-7, (10-6) to cut the lead to 7-3.
Anderson, who played at the University of Illinois, lost the Wimbledon final to Djokovic.
Results from the 2018 Laver Cup on Saturday:
Europe 7 World 5
Alexander Zverev (Europe) bt John Isner (World) 3-6, 7-6 (8/6), 10-7 (10-point tie-break)
Roger Federer (Europe) bt Nick Kyrgios (World) 6-3, 6-2
Kevin Anderson (World) bt Novak Djokovic (Europe) 7-6, 5-7, 10-6
Jack Sock/Nick Kyrgios (World) bt Grigor Dimitrov/David Goffin (Europe) 6-3, 6-4