US PGA champion Justin Thomas and Australia's Marc Leishman share the lead after day three of the Dell Technologies Championship, where a show of petulance proved costly for Sergio Garcia.
Garcia slammed his putter into a sprinkler head after badly misjudging an eagle attempt on the short par-four fourth at TPC Boston, altering the loft and lie of the club.
Under Rule 4-3b, Garcia was not allowed to use it again for the rest of the round, although the Masters champion did at least hole his birdie putt from 13 feet with a fairway wood.
But after using either his driver or a long iron on the greens on the remaining 14 holes, Garcia struggled to a four-over-par 75 which ended in miserable fashion when a dreaded shank led to a double-bogey seven on the last.
It is not the first time this season Garcia has caused himself problems by losing his temper, the world number seven injuring his shoulder after lashing out at a gorse bush on the fourth hole at Royal Birkdale during this year’s Open Championship.
At two over par, Garcia was 14 shots behind Thomas and Leishman, who shot superb rounds of 63 and 65 respectively despite the wet and windy conditions.
England's Paul Casey was a shot off the lead after a 67, with Open champion Jordan Spieth, Grayson Murray and Adam Hadwin a shot further back on 10 under.
Casey, who held a three-shot lead after 54 holes in this event last year but struggled to a closing 73 and was overhauled by Rory McIlroy, carded five birdies and a solitary bogey in his 67.
Thomas recorded eight birdies in a flawless round, including one from 50 feet on the 12th after deliberately hitting his tee-shot onto the adjacent 13th fairway in order to avoid the controversial new bunkers in the middle of the 12th fairway.
The 24-year-old became the youngest player to shoot 59 on the PGA Tour on his way to winning back-to-back events in Hawaii in January, while he set a tournament record for lowest score in relation to par with a nine-under 63 in the third round of the US Open at Erin Hills.
“You can’t really compare them, they are so, so different rounds, but in terms of ball-striking and overall control of my game that was up there with the best I’ve had all year,” Thomas told Sky Sports.
“I drove it better than I have probably any round this year, hit some great irons, I was putting well — it was overall a great day.”
Playing alongside Thomas, world number one Dustin Johnson carded a 66 to finish nine under par alongside halfway leader Jon Rahm, with Phil Mickelson a shot further back following a 69.
Olympic champion Justin Rose and Rickie Fowler are five shots off the pace after rounds of 69 and 66 respectively.
