Australian Adam Scott edged into a one-stroke lead as thunderstorms disrupted the second round of the St Jude Championship in Memphis.

The world number four had shared the overnight lead on three under with Swede Fredrik Jacobson but improved on that with a 66 which put him just ahead of American Brian Gay and fellow Aussie Andrew Buckle, who played only 15 holes.

Having made his fourth birdie of the day at the 16th, Scott then had to wait more than three hours to play his last two holes because of the thunderstorm but he safely negotiated them to reach seven under.

That was enough to keep him ahead of Gay, who matched the Australian's 66.

Padraig Harrington is destined to miss the cut when play resumes after a second-round 72 left him six over - two adrift of safety.

Jacobson could only shoot a level-par 70 to remain three under par and in fourth, while London Brian Davis added a 68 to yesterday's 70 to move into a share of fifth.

The rain delay earlier in the day meant a large number of players were unable to complete their rounds. One of those having to return early is Jose Maria Olazabal, who was five under for his round — two under for the tournament — after 17 holes.

John Daly's golf has not been the best recently but it was events off the course which were making the headlines. The two-time major winner claimed his wife assaulted him while he slept, with reports suggesting she tried to stab him with a steak knife after an argument.

The 41-year-old, winner of the 1991 PGA Championship and 1995 Open, arrived for his second round at the St Jude Championship in Memphis with red marks on his cheeks and alleged he had been assaulted by his wife Sherrie.

According to reports, Daly called police about 6am on Friday but when they attended Sherrie and the couple's children were absent and officers could not find the knife.

Daly issued a statement saying: "While I slept at home last night, I was the victim of an assault by my wife. I filed a complaint with the Shelby County Sheriff's Office. They are investigating, and I'll have no further comment on the matter while they pursue their investigation.

"My only concern at this point is for the safety of my children and myself and we are working closely with local authorities and PGA TOUR security officials to assure appropriate safeguards."