Graeme McDowell and Darren Clarke trail leaders at Valspar Championship

McDowell lies seven shots behind early clubhouse leaders Keegan Bradley and Ken Duke who finished the day on four-under.

Darren Clarke finished with a six-over-par 77 in Florida.

Jordan Spieth’s opening round has left him way back on five-over.

Meanwhile, Michael Hoey is struggling to make the cut at the True Thailand Open following a bad start to his opening round.

Hoey carded three bogeys in his first five holes but finished with a one over par round of 73 on the Black Mountain course.

The Belfast golfer recovered with birdies on the sixth and 10th holes and lies nine shots off the lead held by American Peter Uihlein.

Uihlein was forced to withdraw from the Omega Dubai Desert Classic last month due to the problem, but returned to action at the Maybank Championship Malaysia two weeks later and finished ninth in Kuala Lumpur.

The former European Tour rookie of the year then finished fourth in the Perth International – where he also led after round one – and carried that form into the opening day in Hua Hin with nine birdies and one bogey in a brilliant 64 at Black Mountain Golf Club.

Uihlein, who enjoyed a holiday in Phuket with former Ryder Cup star Nicolas Colsaerts last week, revealed that his expectations were low after struggling in practice for the last three days.

“Last week I had a nice vacation and didn’t touch a club, which was nice,” American Uihlein told European Tour Radio. “You come up here with a clean slate and a fresh start.

“I hit it so badly on Monday, Tuesday and Wednesday, so I was kind of bummed.

So it’s nice to do this today. Once the tournament got going, I just relaxed.

“I putted well and the putter is still hot, which is nice.”