After finishing the British Superbike Championship season with three fifth places at Oulton Park, Guintoli was signed up for another season with the Worx Crescent Suzuki squad. But when Max Neukirchner suddenly left Suzuki to join Honda, Guintoli was drafted in as his replacement for the 2010 season. Guintoli then rode the final World Superbike Championship round of the 2009 season in Portimão finishing tenth in the second race. He was competitive at the opening round, but was disappointed with his own performance at round two in Portugal, where he took a best finish of ninth on a bike that teammate Leon Haslam rode to a victory. He did not finish as high as fourth again until round nine, but had scored points in every race at this stage.