Michael Dunlop admitted he made an "error" with his bike set-up after finishing third in Saturday's Isle of Man Senior TT.
The Ballymoney rider proved no match for eventual winner Peter Hickman who surged to his fourth win of the meeting with a dominant display in the Superbike class.
Dean Harrison finished second, some 19.9 seconds behind Hickman, with Dunlop a further 20.4 seconds back in third.
