Lewis Hamilton beat Esteban Ocon to take top spot in the final practice session for Formula 1's Belgian Grand Prix, where light rain at Spa meant little running took place.
Valtteri Bottas and Max Verstappen finished fifth and sixth after abandoning their final qualifying simulation efforts, as Ferrari's Spa misery continued with Charles Leclerc finishing in P17 and Sebastian Vettel last in FP3.
Much of the rubber laid down during the opening practice sessions was washed away during an intense thunderstorm, which was so severe it caused the Porsche Supercup practice session to be red flagged on Friday evening.
That meant few cars took to the track in the early stages, with only the Haas cars circulating during the opening minutes - once several other runners had completed a solitary installation lap.
Kevin Magnussen and Romain Grosjean moved to the top spots straight away as a result, with the former ahead on a 1m 45.984s on the medium tyres, as they tried to make up for the lack of running they were able to complete on Friday due to their power unit changes.
But after 15 minutes they returned to the pitlane, leaving no cars on track for a long period as the rain continued to fall gently at various points around the long Spa lap.
McLaren's Lando Norris eventually led the pack onto the track after 20 minutes, with several runners - including the Mercedes duo and Verstappen - heading out on the soft rubber straight away.
Norris initially lowered the P1 benchmark on the mediums before he was moved down by Alex Albon's 1m45.092s - also on the yellow-walled rubber.
Hamilton then put in a 1m44.422s, which was immediately supplanted by Bottas's 1m43.813s, which put the gap between the Mercedes drivers at 0.6s - although Hamilton was able to lower this to 0.3s with a second run on his first set of softs.
Verstappen slotted himself into the gap between Bottas and Hamilton before a long lull in action took place as spots of rain returned.
After a 15-minute delay with no cars on track, the pack headed back out with eight minutes of the one-hour session remaining - apart from Magnussen - all on the soft tyres, which only a minority had tried by that stage.
Ocon blasted to the session's best time in the first sector, which suggests Renault has opted to go for a lower downforce package to gain time in Spa's long acceleration zones, as he lowered the best time to a 1m43.485s.
But Hamilton returned Mercedes to the top spot with a 1m43.255s on his final run on the softs, to lead FP3 by 0.230s over Ocon.
Bottas and Verstappen did not set better times in the final flurry of action, with the former abandoning his lap after locking his right-front at La Source and then nearly losing the rear of his W11 as he slid wide on the exit kerb.
Verstappen was caught in the massive traffic jam at the Bus Stop chicane that built up as the pack all fought for space for their final laps and he did not improve his time on his subsequent laps.
That meant Norris and Albon finished third and fourth after their late gains on the softs, with Daniel Ricciardo taking seventh behind Bottas and Verstappen - 0.488s behind Ocon's P2 time.
Lance Stroll, Carlos Sainz Jr and Sergio Perez rounded out the top 10.
Leclerc and Vettel were both hampered by the traffic late on, with Vettel also having a wild final lap to put in a 1m45.420s that left him last.
The four-time F1 world champion had also been forced to catch a big oversteer moment as he ran through Les Combes earlier in the session, locking his left-front as he stopped his SF1000 running off to the right of the track.
Belgian GP - FP3 Result
|1||Lewis Hamilton||Mercedes-AMG Petronas Formula One Team||1m43.255s|
|2||Esteban Ocon||Renault DP World F1 Team||0.230s|
|3||Lando Norris||McLaren F1 Team||0.386s|
|4||Alexander Albon||Aston Martin Red Bull Racing||0.476s|
|5||Valtteri Bottas||Mercedes-AMG Petronas Formula One Team||0.558s|
|6||Max Verstappen||Aston Martin Red Bull Racing||0.641s|
|7||Daniel Ricciardo||Renault DP World F1 Team||0.718s|
|8||Lance Stroll||BWT Racing Point F1 Team||0.733s|
|9||Carlos Sainz Jr.||McLaren F1 Team||0.751s|
|10||Sergio Perez||BWT Racing Point F1 Team||0.925s|
|11||Pierre Gasly||Scuderia AlphaTauri Honda||1.253s|
|12||Daniil Kvyat||Scuderia AlphaTauri Honda||1.288s|
|13||Nicholas Latifi||Williams Racing||1.516s|
|14||Kevin Magnussen||Haas F1 Team||1.586s|
|15||Romain Grosjean||Haas F1 Team||1.589s|
|16||Kimi Raikkonen||Alfa Romeo Racing ORLEN||1.677s|
|17||Charles Leclerc||Scuderia Ferrari||1.892s|
|18||George Russell||Williams Racing||1.902s|
|19||Antonio Giovinazzi||Alfa Romeo Racing ORLEN||1.935s|
|20||Sebastian Vettel||Scuderia Ferrari||2.165s|