They will play No. 18 and if they tie, they’ll alternate between the 10th and 18th holes until someone wins Sunday.
Oosthuizen was in the lead for most of the day after holing out from the second fairway for a double-eagle 2, only the fourth albatross in the history of the tournament.
Watson caught the South African by making four consecutive birdies on Nos. 13 through 16.
Lee Westwood, Matt Kuchar, Phil Mickelson and Peter Hanson tied for third at 8 under.
This is the first Masters playoff since 2009, when Angel Cabrera beat Chad Campbell and Kenny Perry.
THIS IS A BREAKING NEWS UPDATE. Check back soon for further information. AP’s earlier story is below.
By John Solomon
How the government's punishing of the exposure of official wrongdoing can linger for years
Independent voices from the TWT Communities
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