SAN FRANCISCO —
Spieth made six birdies, including a seven-iron to four feet on the par-three 13th for some breathing room, and closed out Finland's Mikko Ilonen on the 16th hole at TPC Harding Park.
As usual, plenty of big names lost early.
Instead of going home, they have some hope.
The format this year is 16 four-man groups in round-robin play, with the winner of each group advancing to the round of 16 on the weekend.
The 32 losers still had two more matches, but Thursday's round became even more critical. It's possible they can be eliminated Thursday. It's possible their Friday matches will be meaningless. And yet all of them can still advance, although they will need some help.
"A lot has to work out now," Kuchar said.
Spieth played as though nothing had changed from a year ago. He told caddie Michael Greller not to check the painted dots on the greens that would indicate the pin positions for the Thursday rounds.
"I wanted us to look at it like it was win or go home," Spieth said. "I think I did see him checking on a couple of them. But I wanted that to be our mind-set. There's going to be a lot of 2-1 scenarios in each group, so it's best not to worry about anything else."
Rose, coming off a victory Sunday in New Orleans, still wasn't sure what to think about the new format.