Big guns Ian Hutchinson and Michael Dunlop whetted the appetite for Saturday's Isle of Man TT RST Superbike race as both riders unofficially broke the outright lap record on Friday evening.
Morecambe Missile McGuinness set the fastest ever lap of the Mountain Course on his way to victory in last year's Senior race at 132.701mph as he slowed for fuel on lap two.
However, Bingley Bullet Hutchinson caused a sensation as he shattered the benchmark on his Tyco BMW Superstock machine on his first flying lap during practice on Friday, raising the bar to 132.803mph (17m 02.781s).
Dunlop, who went out on his Hawk Racing Superbike, opened up at 124.806mph before also going under McGuinness's record with a speed of 132.754mph on his second lap.
Even more impressive was Dunlop's final lap on Friday evening, when the 27-year-old clocked 132.413mph on his Superbike from a standing start to pave the way for the first ever 133mph of the 37.73-mile course on Saturday.
On his MD Racing BMW Superstock machine, Dunlop lapped at 131.879mph from a standing start to keep snapping at Hutchinson's heels, with each rider attempting to outdo the other.
Dunlop was clear in the Superbike times thanks to his 132.754mph mark, but Yorkshire rider Hutchinson was poised behind him after setting his best speed at 132.413mph, with Dean Harrison third quickest on the Silicone Engineering Kawasaki (129.96mph).
Dunlop starts 20 seconds behind Hutchinson on the road on Saturday in the Superbike race and a blistering showdown is on the cards between the pair, although it would be foolish to write off Honda Racing's McGuinness, who will set off down Bray Hill first at number 1 ahead of fellow contender and last year's winner Bruce Anstey.
McGuinness was sixth fastest on his Fireblade on Friday at 129.206mph, although the 23-time winner has a 131mph lap in the bank from Thursday.
Michael Rutter on the Bathams SMT BMW was fourth quickest at 129.613mph ahead of Conor Cummins (Honda Racing), who managed a lap of 129.499mph.
Norton rider David Johnson set another impressive lap on the SG5 machine at 128.533mph and was also quickest through the Sulby speed trap at 194.5mph.
Kiwi Anstey went round at 127.252mph on the Valvoline Padgetts Honda RC213V-S but admitted he was feeling stiff following his tumble at Keppel Gate on Thursday.
Hutchinson and Dunlop were the standout names on the Superstock time sheets with Harrison again showing strongly on the Silicone Engineering Kawasaki in third following a speed of128.947mph, which put him ahead of Northern Ireland's Lee Johnston on the East Coast BMW (128.607mph).
James Hillier (Quattro Plant Muc-Off Kawasaki) and McGuinness on the EMC Bet Victor Honda were next, lapping at 128.134mph and 128.092mph respectively.
Peter Hickman did 127.972mph on the JG Speedfit Kawasaki.
Harrison topped the Supersport times following a standing start lap of 126.249mph to head Ramsey Rocket Cummins on the Valvoline Padgetts Honda (124.353mph) and McGuinness on the Jackson Honda (123.863mph).