Miami - Australian star Jason Day made a tearful withdrawal Wednesday from the World Golf Championship-Dell Match Play to be with his cancer-stricken mother while Rory McIlroy and Jordan Spieth lost their openers.
Day, the defending champion, broke down in tears in Austin, Texas, after withdrawing from his first round match against American Pat Perez after only six holes at Austin Country Club before later revealing the personal anguish that led to his concession.
World number two McIlroy, seeking his second title in three seasons, lost 2 and 1 to Denmark's Soren Kjeldsen and Japan's Hideto Tanihara downed fifth-seeded Speith 4 and 2, while top-ranked Dustin Johnson downed fellow American Webb Simpson 5 and 3.
The defeats do not end the title hopes for McIlroy and Spieth thanks to group-stage play conducted through Friday instead of the typical match-play bracket format.
Day, 29, said he was pulling out to be with his mother, Dening Day, who is facing surgery on Friday to remove a cancerous growth from her lungs.
"She's going in for surgery this Friday and it's really hard to even comprehend being on the golf course right now because of what she's going through," Day told reporters through tears.
"It's been really hard to play golf. It has been very, very emotional as you can tell," added Day, whose father Alvin died of cancer in 1999 when the golfer was 11.
"I've already gone through it once with my dad and I know how it feels. It's hard enough to see another one go through it as well. As of now I'm going to try and be with my mum for this surgery and make sure everything goes right with her.
"It's been a very, very hard time for me to be even thinking about playing golf. It's been weighing on me emotionally for a while.
"And although my mum says not to let it get to me, it clearly has. I just need some time away with her to make sure everything goes well because she's the reason that I'm playing golf today. Family's first."
Day was in Group 3 with fellow Aussie Marc Leishman, who opened with a 3-and-2 win over England's Lee Westwood.
This marks the third year of group play to open the event, ensuring top names no longer risk being ousted on day one. Knockout play opens with 16 group winners on Saturday morning.
McIlroy was 1 up with five holes remaining after three birdies in a row to win holes but Kjeldsen made four consecutive birdies to seize the victory, his last three approaches landing within four feet of the cup.
"I played well," McIlroy said. "If I had played anyone else, I might have won. Soren played great. I think I have to give him credit. He played really, really well from the first hole."
"He's such a great player, so I knew I had to go and play well," Kjeldsen said. "I had to focus on what I was doing and I played really well today. My mindset was if I go and shoot a good score, he has to play well to beat me. I know he's capable of that but I managed just to squeeze it in."
Tanihara, making his debut in the event, sank a 15-foot birdie putt to go 1-up after seven holes, then won the 10th by sinking his approach and took three of the next holes to seal the victory over Spieth, who couldn't manage a birdie past the first hole.
"I was looking forward to playing," Tanihara said. "I knew if I brought my 'A' game, I could probably compete against him.
"I wanted to see how a top player would play and I was just looking forward the whole day. Trying to win the whole tournament, you have to go through tough guys. So just happy to get this win."
Results from Wednesday's opening round of the World Golf Championships-Dell Match Play at Austin (Texas) Country Club (USA unless noted):
Dustin Johnson bt Webb Simpson 5&3
Martin Kaymer (GER) bt Jimmy Walker 3&2
Soren Kjeldsen (DEN) bt Rory McIlroy (NIR) 2&1
Gary Woodland bt Emiliano Grillo (ARG) 3&2
Pat Perez bt Jason Day (AUS) by withdrawal
Marc Leishman (AUS) bt Lee Westwood (ENG) 3&2
Hideki Matsuyama (JPN) and Jim Furyk halved
Louis Oosthuizen (RSA) bt Ross Fisher (ENG) 4&3
Hideto Tanihara (JPN) bt Jordan Spieth 4&2
Ryan Moore and Yuta Ikeda (JPN) halved
Justin Thomas bt Chris Wood (ENG) 2&1
Kevin Na bt Matthew Fitzpatrick (ENG) 5&4
Sergio Garcia (ESP) and Shane Lowry (IRL) halved
Jon Rahm (ESP) bt Kevin Chappell 3&2
Alex Noren (SWE) bt Thongchai Jaidee (THA) 3&2
Bernd Wiesberger (AUT) bt Francesco Molinari (ITA) 2 up
Patrick Reed and Jason Dufner halved
Brooks Koepka bt Kevin Kisner 6&5
Tyrell Hatton (ENG) bt Charles Howell 2&1
Rafa Cabrera Bello (ESP) bt Wang Jeung-Hun (KOR) 4&3
Kim Kyung-Tae (KOR) bt Danny Willett (ENG) 4&2
Russell Knox (SCO) bt Bill Haas 3&2
Paul Casey (ENG) bt Joost Luiten (NED) 2&1
Charl Schwartzel (RSA) bt An Byeong-Hun (KOR) 6&5
Bubba Watson bt Jhonattan Vegas (VEN) 1 up
Thomas Pieters (BEL) bt Scott Piercy 3&2
Phil Mickelson bt Kim Si-Woo (KOR) 5&3
Daniel Berger bt J.B. Holmes 7&5
Branden Grace (RSA) bt Andy Sullivan (ENG) 4&2
William McGirt bt Brandt Snedeker 2 up
Matt Kuchar and Brendan Steele halved
Tommy Fleetwood (ENG) bt Zach Johnson 1 up