Charles Leclerc has topped the final practice session at Monaco, setting a 1:11.265 to just finish ahead of Mercedes' Valtteri Bottas.
However, Leclerc is under investigation for a virtual safety car infringement during the session, with the Stewards confirming it would look at the issue following the chequered flag.
The virtual safety car was deployed when Sebastian Vettel crashed at Turn 1 early on in the session.
Vettel locked up as he turned the wheel for the first corner of the lap, and couldn't slow the car in time before making contact with the barrier, damaging his front wing and front suspension.
Vettel managed little running during the session, which won't spike his confidence heading into the qualifying session later this afternoon.
Lewis Hamilton was third for Mercedes, just over two-tenths down on Charles Leclerc. The Red Bull duo were fourth and fifth, with Max Verstappen leading Pierre Gasly by two-tenths of a second.
Antonio Giovinazzi, who has been showing strong pace over the weekend, ended the session as the 'best of the rest' driver in sixth place, ahead of Toro Rosso's Daniil Kvyat.
Giovinazzi's teammate Kimi Raikkonen also finished inside the top ten, as he slotted into ninth behind Kevin Magnussen.
Alexander Albon followed the Haas driver, beating the two Renault's of Nico Hulkenberg and Daniel Ricciardo to round out the top ten ahead of qualifying.
Vettel, who set his fastest time early on in the session, ended up in 14th behind Romain Grosjean in the Haas.
Both McLaren and Racing Point seemed to struggle for pace during the session, as the Woking squad headed the Lawrence Stroll-owned outfit in 15th and 16th.
Carlos Sainz got the better of his rookie teammate Lando Norris, while the provisional penultimate row saw Sergio Perez ahead of Lance Stroll.
Stroll had a major lock up at Turn 1 during the 60-minute outing but avoided the barriers to continue on his way. Williams rounded out the timesheets, as Robert Kubica, who has two podium finishes to his name around Monaco, headed George Russell.