It wouldn't take long for his efforts to be rewarded as Staring would also come down at turn 11 in his attempts to keep up with the BMW rider. Despite his attempts to get going again, Staring would concede defeat to accept a retirement that effectively puts him out of the title chase.
With his rivals down and out, Barrier coasted to the finish line to claim his fourth victory of the season, a result that reduces La Marra's advantage in the standings to just six points with two races remaining. Staring and Guarnoni, meanwhile, are still mathematically in the hunt, but 33 and 37 points adrift respectively with only 50 up for grabs.
With three of the four front runners failing to finish, Kev Coghlan took full advantage to claim his maiden Superstock 1000 podium on the DMC Ducati 1199 Panigale, the Briton crossing the line in a fine second position.
He was followed home by Alpha BMW rider Markus Reiterberger, who had the honour of breaking his own podium duck on home soil, while Staring'ss team-mate Leandro Mercado was another to post a new personal best to raise some smiles for Pedercini Kawasaki in fourth.
Monza race winner Lorenzo Savadori finished a quiet fifth place on the sole surviving Barni Ducati, just ahead of Fabio Massei, while Christoffer Bergman, Ondrej Jezek, Marco Bussolotti and Matthieu Lussiana all capitalised on the drama ahead to secure top ten finishes.