Los Angeles - Jim Herman credited "a good talking to" from US President Donald Trump with helping him lift his game enough to take the halfway lead on Friday at the PGA Tour's Barbasol Championship.

Herman, seeking a second US tour title to go with the Houston Open trophy he claimed in 2016, had eight birdies and a bogey in his seven-under 65 at Keene Trace Golf Club in Nicholasville, Kentucky.

His second straight 65 put him on 130 - one stroke in front of fellow American Bill Haas who carded a 66.

"Everything seems to be working this week, a nice change-up. I haven't really been playing very well," said Herman, who was an assistant club pro at Trump National Bedminster in New Jersey in 2006/07 and has played numerous rounds with the US president.

That included one a couple of weeks ago, Herman said.

"I got some advice from someone pretty high up - he gave me a good talking to and told me to use a different style if it's not working.

"That was the president of the United States," added Herman, just to clarify, and the changes he has since made to his putting are paying off.

"I'm rolling the ball great," said Herman, who hasn't had a top-10 finish since 2017.

"I'm hitting a lot of greens and making some putts, that's always a good combination."

Haas followed his opening 65 with a 66 - rolling in a 45-foot eagle at his penultimate hole, the par-five eighth.

David Toms carded a 64 to join a group of four players sharing third on 132, alongside D.J. Trahan, Kelly Kraft and Kramer Hickock - who all shot 67.

Toms, 52, drained a 13-foot eagle at the fifth, his 14th hole of the day, and heads into the weekend in contention to become the second-oldest player to win on the PGA Tour. He would be three months older than Sam Snead was when he won the 1965 Wyndham Championship.

J.T. Poston, who surged to the first-round lead in this event being played opposite the British Open at Portrush with a course record 62, ballooned to a 73 to fall into a tie for 18th, five shots off the lead.

Canada's Nick Taylor, who went into the round one shot behind Poston, carded a 72.

Leading scores after Friday's second round of the PGA Tour's Barbasol Championship in Nicholasville, Kentucky (par-72, USA unless noted):

130 - Jim Herman 65-65

131 - Bill Haas 65-66

132 - D.J. Trahan 65-67, Kelly Kraft 65-67, David Toms 68-64, Kramer Hickok 65-67

133 - Sebastian Munoz (COL) 65-68, Austin Cook 67-66, Jose de Jesus Rodriguez (MEX) 68-65, Wes Roach 64-69

134 - Roberto Castro 65-69, Charlie Beljan 68-66, Chase Wright 67-67, Hank Lebioda 70-64, Cody Gribble 68-66, Martin Laird (SCO) 68-66, Tom Lovelady 69-65

135 - Billy Hurley 68-67, Josh Teater 65-70, Zack Sucher 70-65, Robert Garrigus 70-65, Case Cochran 71-64, Dominic Bozzelli 67-68, Nick Taylor (CAN) 63-72, Freddie Jacobson (SWE) 67-68, J.T. Poston 62-73