Carlos Sainz stole the spotlight in the opening practice at the Monaco Grand Prix, securing the top spot for Ferrari.
Following closely behind was the seasoned veteran Fernando Alonso representing Aston Martin, displaying his impressive skills on the iconic street circuit.
Lewis Hamilton, equipped with a significant Mercedes upgrade, claimed a respectable third place before the session was cut short due to Alex Albon's crash.
Hamilton was ahead of both Red Bulls - with Sergio Perez fourth and world champion Max Verstappen, who complained on multiple occasions about the handling of his Red Bull, sixth. The Ferrari of Charles Leclerc split the Red Bull pair.
The red flags were deployed in the closing minutes when Albon lost control of his Williams through the opening Sainte Devote corner.
The London-born Thai slammed into the wall, but, despite admitting to banging his knees, he emerged relatively unscathed from the 100mph accident.
The same could however, not be said for Albon's Williams following significant damage to the left-hand side of his machine.
After giving up on this season's car on the eve of the opening race, Mercedes have arrived for the sixth round of the season in the sun-cooked principality with a new concept.
The Silver Arrows have abandoned their controversial zero-sidepod design, and introduced a new front suspension, new floor and cooling system in a change of development on a car which has contributed to the longest losing streak of Hamilton's career.
On Sunday, it will be 539 days since Hamilton last stood on the top step of the podium at the penultimate round of the contentious 2021 season in Saudi Arabia.
And although Hamilton ended the opening running 0.663 sec behind Sainz, the seven-time world champion and his Mercedes team might take confidence from finishing ahead of both Red Bull drivers.
Verstappen and team-mate Perez are the only men to have won a race this year, but their rapid Red Bull is not necessarily suited to the narrow and slow-speed confines of the unique Monte Carlo configuration.
Sainz lapped a third of a second quicker than Alonso, with Verstappen 0.872 sec off the pace. Hamilton's team-mate George Russell was only 15th, 1.6 sec back.
Elsewhere, Lando Norris finished seventh for McLaren as Nico Hulkenberg completed the fewest laps after he spun his Haas at the chicane on the exit of the tunnel.
Second practice gets under way at 17h00 local time (16h00 UK).
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