Marco Melandri (Aruba.it Racing – Ducati) had led the second session at Motorland Aragon on Friday and his 1’55.652 lap time was enough to keep him on top in FP3, after the overnight rains arrived halfway through the final session of the opening day.
Jonathan Rea (Kawasaki Racing Team) proved to be second fastest overall, just 0.039 seconds behind Melandri, with Tom Sykes (Kawasaki Racing Team) 0.197 seconds adrift of the lead.
Ever-competitive Ducati rider Chaz Davies (Aruba.it Racing – Ducati) ended day one fourth, from the gradually gelling package of Jordi Torres and his MV Agusta Reparto Corse F4. He was the first of the leading riders to improve his best time in FP3 before the rain came back on.
Buriram podium finishers Alex Lowes (Pata Yamaha Official WorldSBK) and Michael van der Mark (Pata Yamaha Official WorldSBK) were sixth and seventh respectively, with top independent rider, and genuine contender for race wins, Xavi Fores (Barni Racing Team Ducati) eighth at his home round.
Lorenzo Savadori (Milwaukee Aprilia) held off the attentions of Leon Camier (Red Bull Honda World Superbike Team), the Italian and British riders ending up ninth and tenth respectively. Camier now runs a Magneti Marelli electronics system on his Fireblade after a successful test at Assen in the aftermath of the Thailand round.
Michael Ruben Rinaldi (Aruba Racing IT Ducati Junior Team) was 11th in his first competitive on-track ride of 2018: he will only contest the European rounds on his third factory bike. Davide Giugliano (Milwaukee Aprilia), standing-in for the recovering Eugene Laverty (Milwaukee Aprilia), was 12th fastest of the 21 riders present in Spain.
Jake Gagne (Red Bull Honda World Superbike Team) was 14th and PJ Jacobsen (TripleM Honda World Superbike Team) 19th.