Rory McIlroy shot a 63 on the second day of the Charles Schwab Challenge in Texas to put himself in contention for golf's first tournament back following the coronavirus suspension.
The world number one started the second day on two under par and hit an eagle on the 10th hole before finishing on nine under in Fort Worth in a round that also featured six birdies and a bogey.
McIlroy was tied for 39th after the opening day at Colonial Country Club but picked up the pace in the second round, flirting with the course record before taking a bogey at his last hole - the ninth.
Harold Varner III, who led jointly with Justin Rose after a first-round 63, started his second round with a triple-bogey after his tee shot landed on a bridge.
But the American recovered to post a 66 which put him two shots ahead of McIlroy and compatriots Collin Morikawa and Xander Schauffele.
Jordan Spieth was a shot off Varner at the halfway stage despite four-putting the 12th hole. He also bogeyed the 13th but followed it up with two birdies for a second successive 65.
Bryson DeChambeau is also just a shot off the pace after a flawless 65.
Graeme McDowell and Shane Lowry both missed the cut, McDowell by one shot and Lowry by four. Lowry carded a 73, while McDowell scored a 70.
Overnight co-leader Justin Rose is a shot behind McIlroy, level with Justin Thomas, Branden Grace , Daniel Woodland and Gary Berger after shooting 69.
McIlroy's seven-under-par suggests he has adjusted to golf without the galleries, though the Down man says the silence that meets his birdie putts took some getting used to.
"I think even yesterday, once we sort of got into the flow of the round, things started to become more normal," McIlroy said.
"When that first birdie putt went in and I didn't get a clap ... like my hand was trying to go up to wave to someone in the gallery, but there's obviously no one there. But once you get into it, it's the same.
"I'd love there to be fans here this week. I think this tournament deserves to have fans but hopefully we can get back to playing in front of some big crowds soon."