Tom Sykes swept to the top of the timesheets in second free practice for the Bennetts British Superbike Championship at Croft, although an accident for Shane Byrne threatens to rule him out of qualifying and possibly the races too.
The championship leader, who can wrap up the title this weekend, crashed heavily at the Chicane to cause the session to be red flagged with ten minutes remaining.
It has since been revealed that Byrne has suffered soft tissue damage to his shoulder, as well as lose a tooth, problems that could rule him out of qualifying when he undergoes a medical test tomorrow. His participation in the races could also be in doubt now.
Meanwhile, newly-announced Yamaha World Superbike rider Sykes went quickest, although his lap of 1min 21.155secs was slower than Byrne's effort in the morning.
He was followed by HM Plant pairing Leon Haslam and Cal Crutchlow, just one and two tenths adrift respectively, while Karl Harris and Leon Camier rounded out the top five.
Yet again, the top ten witnessed no surprise names, with Michael Rutter ahead of Byrne, who remained seventh despite his crash, James Ellison and Simon Andrews, while Cup runner Gary Mason provided the only real unusual appearance in tenth.
Elsewhere, series newcomer Jason O'Halloran ended his first day of BSB competition in a satisfactory 18th as he gets to grips with British circuits and the SMT Honda.