After a 2-inch snowfall threw the tournament off schedule Wednesday, tournament officials plan to play the third round and the quarterfinals on Saturday. The semifinals and championship match will be take place Sunday.
Watson, the long-hitting left-hander who defeated Oosthuizen in a playoff to win the Masters last year, needed four extra holes to defeat Jim Furyk and set up a third-round meeting with Jason Day.
Watson had a 1-up lead heading to the 18th hole, where he hit a spectacular approach shot that finished two feet from the cup. Furyk answered by putting his second shot to within five feet and he made the birdie putt. That forced Watson to hole his putt to win the match, but he missed it and they went into a sudden death playoff.
Day also had to work overtime to defeat PGA Tour rookie Russell Henley in 19 holes. Henley made a 12-foot birdie putt at the 18th hole to force overtime, but Day birdied the first extra hole.
Piercy pulled off the biggest surprise in the second round by winning four of the first five holes and eventually drubbing Donald 7-and-6. Oosthuizen was eliminated by Robert Garrigus 3-and-2.
Of the 16 players remaining, seven are from the United States, seven are from Europe, one is from Australia and one is from South Africa.