Eugene Laverty made his first appearance at the top of the timesheets during the first World Supersport test session of the day at Portimao.
The Irishman, runner-up to Cal Crutchlow and race winner at the Portuguese circuit in 2009, mastered the tricky weather conditions to edge out Triumph's Chaz Davies by more than half a second.
Only three riders were able to break the magic two minute marker, with Laverty and Davies being joined by Ten Kate Honda's Michele Pirro, while Friday pace setter Joan Lascorz kept a watching brief in fourth.
Sebastien Charpentier continued to make progress on his return to WSS competition as he went fifth fastest, ahead of Miguel Praia and Fabien Foret. Jason Di Salvo, Bastien Chesaux – who prompted a red flag when he fell in the session – and Katsuaki Fujiwara completed the top ten.