Johnson won the first three holes and was 5-up after nine
holes and steamrolled Webb Simpson 5&3.
"When you get up real early, you just want to keep the momentum
on your side," said Johnson.
Rory McIlroy and Jordan Spieth were surprise losers in their
first round-robin matches at Austin Country Club.
McIlroy, who reached last year's semi-finals, fell 2&1 to Dane
Soren Kjeldsen while Japan's Hideto Tanihara, making his first
appearance at the tournament, routed Spieth 4&2.
Kjeldsen was 1-down with five to play but rattled off four
successive birdies, knocking his last four approaches inside
nine feet, with the last three inside four feet.
"I played well. If I had played anyone else, I might have won.
Soren played great," said McIlroy.
Northern Irishman McIlroy will play Gary Woodland on Thursday
and Argentine Emiliano Grillo on Friday. Woodland beat Grillo
Twice major champion Spieth never led against Tanihara, who has
13 career titles overseas. The American played his last nine
holes in three over, hitting only one green.
"I knew if I brought my 'A' game, I could probably compete
against him," said Tanihara. "I wanted to see how a top player
would play and I was just looking forward the whole day."
Next up for the Texan is a clash with Japan's Yuta Ikeda on
Thursday and Ryan Moore on Friday. Moore halved his match with
Japan's Hideki Matsuyama and U.S. Ryder Cup Captain Jim Furyk
halved, while Brooks Koepka was lights out with the putter in a
6&5 trouncing of fellow American Kevin Kisner.
Day, last year's winner, walked off the course after six holes,
revealing to reporters that he was leaving to be with his
mother, who is having lung cancer surgery on Friday.
"Hard to comprehend being on the golf course right now with what
she's going through," said a tearful Day. "Family is first."
The event is comprised of 16 four-player groups who play
round-robin matches from Wednesday through Friday with the
winners of each group advancing to a single-elimination bracket
at the weekend.
Players receive one point for a win and a half-point for a
(Reporting by Larry Fine in New York; Editing by Frank Pingue)
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