Second round leaderboard:
-13 J Byrd (US) -12 R Imada (Jpn) -11 A Prugh (US), M Laird (Sco), J Senden (Aus), G McNeill (US), N Thompson (US)
Selected others: -10 R Fowler (US), C Campbell (US) -8 D Duval (US)
Laird's best finish this year was second at the Barclays tournament in August
Defending champion Martin Laird hit the joint-best score of the day to end round two of the Justin Timberlake PGA Tour event two shots off the lead.
The Glasgow-born Laird shot a nine-under-par 62 to reach 11 under, two behind Jonathan Byrd in Las Vegas.
Japan's Ryuji Imada is second after equalling Laird's second-round score.
Australian John Senden and Americans George McNeill, Nicholas Thompson and Alex Prugh are also 11 under, with US Ryder Cup star Rickie Fowler one back.
Laird's sole win on the PGA Tour came last year in a play-off at the same Shriners Hospitals for Children Open, promoted by pop star Timberlake.
"It's definitely the type of tournament you just have to keep firing, and even when you're five, six under par, you know that's not good enough," said Laird.
"You've got to keep going at pins, and that's what I did."
The 27-year-old lost out in a play-off to American Matt Kuchar after a disappointing finish to his final round at the Barclays FedEx Cup event in August.
The Scot had led by five shots at one stage on the final day but three-putted from inside 25 feet at the 18th.