Superbike World Championship leader Jonathan Rea responded to the pace of the Ducati riders in first practice by topping the timesheets in second practice in Aragon.
Kawasaki rider Rea, who heads the standings by 10 points from Aprilia's Leon Haslam, could only manage fifth in the first session with a time of one minute and 52.792 seconds.
The Ducati duo of Chaz Davies (1:52.009) and Xavi Fores (1:52.365) led the way in that session, Suzuki's Alex Lowes (1:52.638) rounding off the top three.
But Rea bounced back well in second practice as he overhauled Tom Sykes (1:51.379) in the final minute of the session to post a time of one minute and 51.234secs.
Davies (1:51.582) was third ahead of Fores (1:52.000), with Haslam (1:52.096) completing the top five.