Southampton - Jordan Spieth's meticulous preparations for the 118th US Open included a just-in-case look at the forecast for next Monday, the American unaware that the US Golf Association has scrapped its traditional 18-hole playoff.
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"It's the first I've heard of that being an option," a surprised Spieth said Tuesday as he spoke to reporters at Shinnecock Hills.
The USGA announced in February that it was switching to a two-hole aggregate playoff to decide the US Open -- should 72 holes fail to produce a winner.
"Two holes will allow a player to recover from any single mistake, and at the same time, provide a memorable, and perhaps dramatic, experience for all involved," USGA chief executive Mike Davis said at the time.
In 117 prior US Opens, the championship has been decided by a playoff 33 times - with those before 1931 played over 36 holes.
Tiger Woods was the most recent US Open playoff winner, defying leg injuries to beat Rocco Mediate at Torrey Pines in 2008 in the first hole of sudden death on Monday after 18 extra holes failed to determine a winner.
"I didn't even know," said Spieth, whose three major titles include the 2015 US Open. "I guess strategy changes a little from an entire round, but I honestly had no idea that it even changed. I was even looking at a weather forecast for Monday, thinking, you know, what's it look like if you happen to work your way into a playoff? So shows you what I know."
Woods said he understood the reason for the change, noting that by choosing a two-hole aggregate for the US Open the USGA insured that each of the four majors maintains a different playoff format.
The Masters uses sudden-death, the PGA Championship a three-hole aggregate and the British Open a four-hole aggregate.
"I understand it because everyone wants to see a result on Sunday," Woods said. It's all about just ending it on Sunday night.
"I'm actually very glad that I didn't have to play any more holes (on Sunday) in '08. I really couldn't go much further on that Sunday. First of all, we've got to see if it happens or not. But I totally understand having a result on Sunday."