(REUTERS) - Reigning Olympic golf champion Justin Rose produced a near "flawless" performance to card a six-under 64 and jump into the halfway lead at the Fort Worth Invitational in Texas on Friday.
After squandering good birdie opportunities at his first four holes, he sank a 10-footer at the next which, in his own words, "took the lid off the hole" at Colonial Country Club.
The Englishman posted a 10-under 130 halfway total to lead Argentinian Emiliano Grillo (67) by a stroke, with American Brooks Koekpa (63) and Japan's Satoshi Kodaira (67) a further two shots back on an international leaderboard.
"I did a lot of good things today. The end of my round got a little scrappy but until the last three holes it was pretty flawless ... about as good as I could play today," Rose said.
Long regarded as one of the game's premier drivers, he was rewarded for his aggression and precision off the tee with an abundance of birdie chances.
He converted seven, but a hotter putter could have made it a really special day.
"I was very comfortable off the tee. Hit a lot of fairways today. If you do that on this golf course you start to get looks (at birdies)," said the world No. 5, who took dead aim at the hole whenever he found himself in the fairway.
This is Rose's first appearance at Colonial since 2010, a change to his schedule made with an eye towards the US Open at Shinnecock Hills in New York next month.
He won the 2013 US Open but has missed the cut in the last two years.
"I feel like if I didn't play here it was going to be a little spotty going into the Open," he said.
"I wanted to play enough golf where I'd have a read on my game going into Shinnecock. All aspects of my game are showing signs."
Koepka fired the best round of the day and, following a closing 63 at the Players Championship two weeks ago, suggested he was ready to defend his US Open title after an injury-interrupted start to the year.
The 28-year-old missed nearly three months, including the Masters, while recovering from a left wrist injury.
"I'm knocking on the door," he said. "I'm right where I was last year. I haven't quite put four days together but I'm pretty damn close. It's something that's going to come soon.
"There's nobody more excited than me to be out here right now. I feel like I'm peaking at the right time."