Samsung Honda's Michael Laverty ended the second free practice session at Snetterton with the top time following a blistering last lap.
Laverty had been vying for the fastest time with Swan Yamaha's Tommy Hill and left it late to clock the best lap in 1m 49.340s to head Hill by three tenths of a second ahead of the fourth round of the MCE British Superbike Championship on Sunday.
The session had to be stopped twice after the red flags were deployed when Tyco Suzuki's Alastair Seeley – the morning pacesetter – crashed at Riches and again when Tom Tunstall's Ducati Panigale suffered an engine blow, dropping oil onto the circuit.
Seeley was unable to improve on his time and his GSX-R1000 but was lucky to escape relatively unscathed after his machine caught fire in the accident.
Rapid Solicitors' Shane Byrne was third fastest, followed by Ian Lowry on the Padgetts Honda and WFR Honda's Alex Lowes.
Tyco Suzuki's Josh Brookes was next ahead of veteran Chris Walker and Graeme Gowland (WFR Honda).
The top ten was rounded out by Patric Muff on the Supersonic BMW and Luca Scassa on the second of Clive Padgett's Hondas.
Noriyuki Haga was 19th ahead of Stuart Easton and Michael Rutter, while Jon Kirkham – back in action following his huge Oulton crash – was 15th fastest on his Samsung Honda CBR1000RR.
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