Northern Ireland's Michael Dunlop wasted no time as he clocked a lap in excess of 121mph to head the leaderboard as practice for the Classic TT roared got underway on Monday evening.
Dunlop lapped at 121.133mph from a standing start on Steve Wheatman's Team Classic Suzuki XR69, completing his sole lap on the machine to top the Classic Superbike times.
Practice got underway at 6.25pm, with Clerk of the Course Gary Thompson advising competitors that there were a number of damp patches around the course at Doran's, Laurel Bank, Glen Helen, Sulby, the 27th Milestone and Governor's following rain earlier in the day.
Steve Mercer, riding the Mistral Kawasaki ZXR750 and Ivan Lintin, who is back in action on the Devitt RC Express Kawasaki after a crash at Scarborough, were second and third fastest, lapping at 118.203mph and 117.995mph respectively.
Lincolnshire's Gary Johnson, a late replacement for the injured Dave Johnson on the Team York Suzuki, lapped at 117.805mph on only his second lap on the bike with the Kawasaki machines of James Hillier (Greenhall Racing) and Dean Harrison (Silicone Engineering) completing the top six.
Alan Thomas from Wales crashed at Waterworks during the Superbike session but was uninjured.
In the Lightweight session, Bruce Anstey was an early retirement at Kirk Michael on his opening lap on the Valvoline Padgetts RS250 Honda.
Welshman Ian Lougher topped the times at 113.363mph on the LayLaw Yamaha ahead of Phil Harvey (107.046mph) and Chris Moore (105.244mph).
In the Senior and Junior session for 500cc and 350cc machines, Michael Dunlop – who replaces the injured Lee Johnston on the Black Eagle MV Agusta machines – was an early retirement.
Morecambe's John McGuinness set the pace on Roger Winfield's Paton as he lapped at 107.089mph on his second lap of the evening to lead last year's winner Dean Harrison (Black Eagle MV Agusta), who set his fastest lap at 106.746mph.
Michael Rutter on the Ripley Land Racing Seeley was third quickest in the session at 104.373mph followed by Manx rider Conor Cummins, who lapped at 103.081mph on his first ride on the second of the Winfield Paton machines.
British championship stalwart Rutter won the Okells 350cc race last year and made a strong start on the Ripley Land Racing Honda last night, leading the Junior class at 99.501mph from fellow Honda riders Jamie Coward (Ted Woof) and Alan Oversby (Davies Motorsport).
Poor weather resulted in Saturday's session being cancelled but practice is now well and truly underway on the Isle of Man ahead of Saturday's opening races.