Tiger Woods' bid for a record fifth Bay Hill Invitational title stalled with a second round one-under 71 that left him seven shots off the lead.
Lucas Glover moved to the top of the leaderboard one shot clear of Australians Robert Allenby and Rod Pampling at the halfway stage in Orlando, Florida on 10-under 134.
Woods, with three wins in his first five tournaments this year, began the day four strokes adrift of joint leaders Bart Bryant and Dean Wilson and looked poised to make a charge when he eagled the par five sixth.
But the world number one never settled into his rhythm on a breezy afternoon at the Bay Hill course, offsetting his eagle and a birdie with two bogeys to leave him with a two day total of three-under 141.
Glover, who notched his first career PGA Tour victory at nearby Disney World last season, returned a five-under 67 for the second consecutive day.
The 26-year-old American began smartly by picking up a stroke at the first and carded six more birdies, the only blemish on his scorecard being a double bogey on the par four 11th.
Pampling surged into contention with the round of the day, carding a bogey free seven-under 65 that included a run off six birdies over eight holes spanning the front and back nines.
Appleby mixed six birdies with a single bogey for a five-under 67 to join Pampling on 135.
Spain's Sergio Garcia, trying to become the first European winner in the 40-year history of the Bay Hill, remained in the thick of the title chase.
He carded a three-under 69 to sit three off the pace at seven-under 137 alongside overnight co-leader Bryant (71).
Ireland’s Darren Clarke carded a second round 70 and, at one under par, has work to do nine shots off the lead.
South African Ernie Els, who became the only non-American to triumph at Bay Hill with his victory in 1998, has plenty of work to do to win the title again after signing for a one-over 73.
Two-under through 11, Els stumbled to the finish with bogeys on three of his final seven holes to find himself six-shots back at four-under 140.
Fiji's Vijay Singh (71) and South African Retief Goosen (73) also struggled as they joined a large group at two-under 142.
