He missed a bucketful of birdie chances on his way to a one-under-par 71 - four strokes behind early pacesetter American Steve Lowery - in the first round of the Bay Hill Invitational in Orlando yesterday.

Montgomerie used his putter 137 times before finishing 38th in last week's Honda Classic. Despite three days of intense practice, he is still bewildered as to why he cannot master American greens.

He said: "I had 33 puts out there and you cannot score better than 71 putting like that. I've hit the ball well since I fell out of the cradle, but I have never had a good putting tournament over here. I am puzzled. Maybe I am not as comfortable in America as I am in Europe.

"I had 17 more putts than Steve Elkington before I lost a play-off to him for the 1995 US PGA title and the same thing happened when I finished five shots behind Mark O'Meara at last year's US Masters. I'm hitting the ball better than most, but my putting is killing me."

Monty, who led out the field, which includes world No 1 Tiger Woods, at 7.45am, was cheered by two birdies in the first five holes, but ended the first nine level.

His third birdie at the 13th with a wedge to four feet was his last success on the greens. The Scot played alongside Lowery, whose home on the fourth fairway at Bay Hill was destroyed by fire three weeks ago. Monty said: "If Steve continues to putt like that, he'll be able to buy a new house at the end of the week."