Ryan Brehm produced the highlight from Thursday's opening round at the Valspar Championship as he drained a late hole-in-one to earn a share of the lead at five under.

Brehm, who collected the only PGA Tour win of his career last season at the Puerto Rico Open, was at three under when he stepped up to the par-three 17th. With one shot on the 196-yard hole he jumped up the leaderboard, securing a par on the 18th to put the finishing touches on a 66.

He is joined at five under by fellow American Adam Schenk and Germany's Stephan Jaeger after a successful first trip around Innisbrook Resort's Copperhead Course.

Just one stroke back in a tie for fourth is Jordan Spieth, coming off three top-20 finishes from his past four starts. The world number 14 and three-time major champion went bogey-free with four birdies, and he is joined at four under by Maverick McNealy and Lucas Glover.

The only other player in the top 10 to finish without a bogey was South Korea's An Byeong-hun, posting a three-under 68 to sit in a five-player group tied for seventh, which also includes Tommy Fleetwood.

Top-20 talents Justin Thomas and Sam Burns headline the logjam at two under, while it was a miserable day for Matt Fitzpatrick.

Fitzpatrick posted a nine on the par-four third hole after finding the water twice, and then went on to also bogey the fourth and fifth. However, he went three under across his next 13 holes to finish at three over and leave himself a chance of making the cut.