British Open 2017: Jordan Spieth, Brooks Koepka, Matt Kuchar Tied for Lead

Jordan Spieth, Brooks Koepka and Matt Kuchar are tied for the lead after the first round of the 2017 British Open at Royal Birkdale, level after each shooting a five-under 65 on Thursday.

The American trio dominated at the links course on Merseyside after testing weather conditions greeted the start of the day.

Rory McIlroy continued to struggle with his overall form, ending his round at one over after a late recovery.

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Spieth set the standard early on with a magnificent round as the weather turned from windy conditions into a sunny afternoon.

The 23-year-old's round of 65 set the standard, giving him the edge over a world-class field.

The American superstar was in magnificent shape with his irons, and he mastered the links course with his brand of exciting golf.

The European Tour highlighted his full round as he claimed the lead:

Spieth carded five birdies in a bogey-free effort, and he will be in full contention to scoop the major if his approach play remains so strong.

It was a stellar day for the United States as Koepka and Kuchar joined Spieth on five under.

Koepka sunk four birdies across six consecutive holes and hit a magnificent eagle on No. 17, but a bogey on No. 16 punctured his card.

The European Tour highlighted the player's sensational putting:

Ian Poulter's return to top form continued as the Englishman shot a three-under 67 for his first effort at the famous course.

Per Daniel Schofield of the Telegraph, after recent troubles with his game, the 41-year-old said:

"Certainly 12 months ago, I was getting very down. It's easy to be down when you feel you're a great player and all of a sudden you're hampered with a bit of injury. You're not getting the results you want. It's very easy to slide away. So I'm proud of the way I've been able to refocus, get things back on the straight and narrow, clear away some of the noise in the background, and get back to really focusing hard on what I need to do to get the level of golf back that I think I can play."

Poulter said he was pleased with his day's work via his official Twitter account:

Rory McIlroy continued to find his best golf difficult to come by as he laboured around the Birkdale links.

Five bogeys in his first six holes was the early story of the Northern Irishman's day, but he salvaged his chances of overall glory on the back nine.

The 28-year-old ended his round on one over, and with more bad weather predicted on Friday, McIlroy remains in contention.

Spieth has arrived in England with the correct mindset and a dangerous game that is ready to attack this course.

The American contingent delivered their brand of consistency and creativity, but several players are producing a great standard, and the tournament is wide open going into Friday.