Peel resident Andrew Pitt could only finish seventh as the World Supersport Championship returned at the weekend following its summer break.
Championship leader Cal Crutchlow won at the Nurburgring in Germany to extend his advantage over Eugene Laverty to 22 points.
Laverty came second with Spain's Joan Lascorz taking third spot.
Defending champion Pitt has struggled to regain the form which saw him top the standings last year and he lost more ground as he looks to defend his title.
He lies seventh in the standings, 116 points behind Crutchlow.
Commonwealth Games athletics squad in positive mood ahead of Glasgow
FC Isle of Man get pre-season underway with summer festival
Swimming: Oscar Maddrell becomes triple British champion
Football: Mixed results for IoM Women in summer series