If it is not one American winning the Open at Turnberry, then it's another American threatening to run away with the Senior Open at Sunningdale. For Stewart Cink in Scotland last weekend, read Fred Funk in Berkshire this week.

Funk, a short, bouncy 53-year-old who walks as though he has springs in the balls of his feet, had putted well for the first 12 holes in his first round, a 64, to open a two-stroke lead.

Then he brought his second round to an exceptional conclusion and widened his lead by holing a wind-assisted eight-iron from a little more than 170 yards for an eagle two on the 18th.

Eagles are rare but not unheard of on the par-five, 492-yard 1st on the Old Course and slightly more common on the par-five, 503-yard 14th. But there are very few on the 18th, a par four of a little more than 420 yards that is played uphill to a green that cannot be seen from the fairway and stands in front of a wonderful old oak tree that is the club's insignia.

No one would describe Funk as a big hitter. It is rather hard to hit the ball a long way when you are 5ft 8in. But he is a good ball-striker and, when he putts well, he is going to score well. His run of 18 putts for 12 holes was the key to Thursday's 64.

His two birdies and that eagle in his last five holes added a nice flourish to his second-round 65, lifting him to 11 under par and a seven-stroke clubhouse lead.

Will it be enough of a lead for him to win today? “If I keep doing what I'm doing and putt as well as I have been putting, I will be hard to catch,” Funk said.

“But even when you are playing really well you can never have enough deposits in the bank, by that I mean eagles and birdies. There are always going to be some withdrawals. You want more deposits and fewer withdrawals.”

Des Smyth could not overcome a bad start, while Denis O'Sullivan had a bad finish containing two double bogeys.

Smyth bogeyed four of the first eight holes and shot 74 to put the brakes on the challenge he mounted with his opening 66. He was on level-par 140.

“I started badly and was always on the back foot,” the Drogheda man said.

He bogeyed the second. “Then I was lucky to make bogey on five because I hit it into the rough and then into the water short of the green. So I made a good five.

“I just played scrappy. I took a bad bogey at seven. I was doing that all day.”

O'Sullivan took his doubles after hitting into bunkers at the 10th and 18th holes. He shot 71 for 139, one under par. He was right up against the face of the bunker at 10. “Then I hit into the trap at 18 off the tee,” the Cork man said. “I hit a great third shot into 15 feet but three-putted it. Awful! I hit the ball really very well. But it does leave a sour taste in your mouth to double bogey the last.”

Christy O'Connor soared to an 80 with a double bogey and nine bogeys on his card.

• Ulster golfers Gareth Maybin (one under) and Michael Hoey (one over) both made the cut in the Swedish Masters while Jonathan Caldwell missed the cut after his disappointing 77 left him four over.

Peter Lawrie and Damien McGrane are the best of the Irish on two under, eight shots behind leader Argentina’s Ricardo Gonzalez. Gary Murphy is one under after carding a 74.