Calcavecchia and Daley steal lead from Couples

Former Open champion Calcavecchia fired a six-under 64 for a 12-under total of 198 to tie with Daley (68), one shot clear of second-round leader Couples (70) and Tom Lehman (66).

Calcavecchia carded three birdies on each half while defending champion Couples cancelled out his three birdies with as many bogeys.

Daley, the first-round leader and 2008 Senior Open champion, looked rattled after two early bogeys but found another gear to grab four birdies in 10 holes from the fifth.