THIRD ROUND LEADERBOARD US unless stated -21 P Mickelson -13 Z Johnson, J Byrd -12 JM Olazabal (Spa) -10 D Barron, S Flesch, JJ Henry Selected others: -7 D Howell (Eng) -6 P Harrington (Ire) +3 L Donald (Eng), I Poulter (Eng)

The American narrowly missed becoming only the second player in over 50 years to hold a 10-stroke advantage going into the final day of a tournament.

He sent two balls into the lake short of the 18th green to dent his hopes.

Mickelson leads compatriots Zach Johnson and Jonathan Byrd with Jose Maria Olazabal another shot back.

Since 1955 only Tiger Woods has taken at least a 10-stroke lead into the final day of a tournament - the 2000 US Open at Pebble Beach.

Mickelson was still satisfied with his third round after birdies at five consecutive holes from the third and, after three-putting the difficult short eighth, he holed from 14 feet on the next to turn in 31.

Further birdies at the 11th, 13th and 14th gave him a 12-stroke lead, but although that was to come back to eight, nobody on the tour has ever lost more than a six-stroke lead on the last day.

In addition, he matched the tournament's lowest 54-hole total after Larry Nelson was 21 under at 195 after three rounds of the 1998 event.

Olazabal, beaten by Mickelson in a play-off last year, saw his victory chances fade a little with a 69.

Luke Donald's round finished even worse than Mickelson's after he landed two pitches into the water for a quadruple bogey nine that dropped him from eighth to 27th.

Also on four under and also round in a disappointing 74 was Ian Poulter. His big setback came much sooner, a double bogey seven on the long fourth.