Formula One world champion Lewis Hamilton was fastest for mourning Mercedes in both Monaco Grand Prix practice sessions on Thursday.
The Briton, excused media duties following the death of Mercedes' non-executive chairman and triple world champion Niki Lauda, lapped the treacherous street circuit with a fastest time of one minute 11.118 seconds in the afternoon on soft tyres.
The five-time world champion, seven points clear of team-mate Valtteri Bottas at the top of the standings after five races, had set the pace on a dry morning with a time of 1:12.106.
Red Bull's Max Verstappen was second fastest in the first session, just 0.059 slower than Hamilton, but sat out much of the afternoon with a suspected water leak.
Bottas ended the day in second place and 0.081 off the pace in a familiar Mercedes one-two.
Between them, Hamilton and Bottas have won every race so far this year with five successive one-twos -- the best ever start to a season -- and are favourites for a sixth on Sunday.
Charles Leclerc, hoping to become the first Monegasque to stand on his home podium since Louis Chiron in 1950, was fourth fastest for Ferrari in the first session with four times champion team-mate Sebastian Vettel fifth.
Vettel moved up to third in the later session, 0.763 off Hamilton's pace, and just ahead of Red Bull's Pierre Gasly while Leclerc dropped to 10th.
Mercedes, Ferrari and McLaren all carried tributes to Lauda on their cars with Mercedes team members also wearing black armbands.
Vettel wore a helmet modelled on one of Lauda's, with the Austrian's name on. Two of Lauda's three titles were won with the Italian team.
Both sessions were free of crashes, although there were the inevitable near-misses on a tight and twisty circuit where cars skim the metal barriers and brush the unforgiving walls.
Gasly had a close escape at the exit to the first swimming pool chicane early on while Robert Kubica spun his Williams at the exit to Casino Square but came to a halt without serious damage.
McLaren had a difficult first session with Carlos Sainz failing to set a lap time and Lando Norris only 15th, but recovered to 13th and 12th later on.
Last year's winner Daniel Ricciardo, who has since moved from Red Bull to Renault, ended the day in 17th place and just behind German team-mate Nico Hulkenberg.
Williams were last and some four seconds off the pace.