Cal Crutchlow continued to set the pace during second free practice at Imola, despite suffering a fall towards the end of the session.
The Briton was going for another quick lap when he came down ten minutes from the end, but his effort of 1min 52.177secs was still enough to keep him in top position when the chequered flag was thrown.
Still, the Yamaha rider is continuing to be kept honest by Kenan Sofuoglu, the Ten Kate Honda rider, who came away from the Imola test in July with the fastest time, just two tenths further back as he looks to regain third in the standings from Joan Lascorz.
The Spaniard himself was just behind in third aboard the Provec Kawasaki, but he remains some eight tenths adrift of Crutchlow.
Local rider Massimo Roccoli was fourth fastest on the Intermoto Czech bike, ahead of Honda counterparts Andrew Pitt and Eugene Laverty, the latter still more than a second behind his chief title rival.
Garry McCoy regained his status as Triumph's top rider in seventh, although new team-mate Chaz Davies can be satisfied to have ended session 12th best himself.