Lewis Hamilton left it late to displace Mercedes team-mate Nico Rosberg at the top of the times in final practice at the European Grand Prix.
Hamilton had a scrappy session, locking up and running wide a number of times on his final set of tyres before beating Rosberg by 0.258 seconds.
The two Mercedes were more than a second clear of the rest of the field, led by Force India's Nico Hulkenberg.
Red Bull's Daniel Ricciardo was fourth from Ferrari's Sebastian Vettel.
The session on the challenging new street track in the Azerbaijani capital Baku ended with a big crash for Hulkenberg's team-mate Sergio Perez, who hit the wall at Turn 15, just as Ricciardo had on Friday.
Perez, who was sixth fastest, ran wide into the barriers on the exit of the corner in an almost carbon-copy of the Australian's accident late in first practice on Friday.
Red Bull's Max Verstappen took seventh, ahead of the McLaren of Jenson Button, separated from team-mate Fernando Alonso by Toro Rosso's Daniil Kvyat and Ferrari's Kimi Raikkonen.
Mercedes hammering everyone
All, though, appeared to be fighting for scraps behind the dominant Mercedes, who have established a huge margin over the rest of the field just a week after being run close by Vettel and Ferrari in Canada.
Hamilton was 1.188secs quicker than Hulkenberg, and the margin - and that over Rosberg - could potentially have been even greater as the Briton's time was set on tyres that had lost their edge.
Hamilton had a number of tries at a fast lap, each time making a mistake somewhere in the long first sector before finally stringing a time together on his fourth attempt.
Ferrari appear to be struggling to make their car work on the low-grip track, after finally delivering on what both they and Mercedes believe is their potential in Canada.
There was a blow for Williams, with Valtteri Bottas having to miss the whole session after his car was damaged when it dislodged a drain cover.
The item flew up and damaged the car's side pod, floor and aerodynamic appendages and the team could not repair it in time to get him out again.
The Finn was third fastest on Friday, but team-mate Felipe Massa could manage only 14th.
Qualifying, which starts at 14:00 BST, will take place in hot and dry conditions, but with the sun beginning to dip at 5pm local time, when the race will also start on Sunday.