Russell breaks down in tunnel during second session
Antonelli crashes as Piastri clips the wall in Q1
Leclerc fastest in final practice as team-mate Hamilton crashes
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Live Reporting
Lorraine McKenna
'Leclerc has looked sharp all weekend'published at 15:32 British Summer Time
15:32 BST
Damon Hill 1996 world champion on BBC Radio 5 Sports Extra in Monaco
Charles Leclerc got about eight-tenths gain on his second run. He's been fantastic and so sharp all weekend, let's see if he's going to be there at the end of qualifying.
There's a good chance he will be if he doesn't make any mistakes.
'Weekend to forget for Stroll'published at 15:30 British Summer Time
15:30 BST
Rosanna Tennant 5 Live F1 reporter in Monaco
I've been watching Lance Stroll looking very disappointed and don't forget he's got that one-place grid penalty as well, so it's a weekend to forget for the Canadian driver. It was interesting to see when Kimi Antonelli hit the barrier, there were shakes of heads in the Mercedes garage, but it was lovely to hear his race engineer checking he was OK.
Kimi Antonelli has made it through to Q2 but we won't be seeing the Italian taking part after that crash.
The stewards are investigating an impeding incident at Massenet between Max Verstappen and Lewis Hamilton. The Red Bull driver was not happy on the team radio, saying the impeding was "massive", Ferrari got in a bit of a muddle as to whether the Dutchman was on a push lap or slowing down and gave the seven-tine world champion the incorrect information.
The only person that would have affected potentially was Lance Stroll. He was on a lap and he had to back off. Gabriel Bortoleto finished already, bad luck for Stroll, I'm not saying he would have qualified, but he was on a lap he had to abort.
Antonelli crashespublished at 15:21 British Summer Time
15:21 BST
The Mercedes has a busted up front left tyre. Kimi Antonelli came out of the tunnel, into that bright sunlight and clipped the barrier, sending him into the wall.
Lando Norris goes second fastest as the likes of Isack Hadjar and the two Alpines are trying to get out of the danger zone. But Kimi Antonelli has hit the wall at the Nouvelle Chicane! That's it for Q1.
There are incidents of impeding popping up all over the track. Race control have noted some blocking between Lewis Hamilton and Max Verstappen and will investigate it after the session.
Leclerc back on toppublished at 15:16 British Summer Time
15:16 BST
The track is evolving and times are tumbling. Charles Leclerc, the driver the home fans want to see on pole, is back on top by 0.156 seconds. The field now are all on the C6 soft tyres.
Lewis Hamilton, meanwhile, is way down in 12th place but is out again to try and improve his lap time.
Piastri quickestpublished at 15:15 British Summer Time
15:15 BST
George Russell has now joined the Q1 party in fourth place but it's Oscar Piastri who has pulled that extra bit of pace out of his McLaren to go above Lando Norris by two tenths. However, the Australian radios through to his pit wall to say he may have hit the wall somewhere.
'Hamilton has a spring in his step'published at 15:13 British Summer Time
15:13 BST
Damon Hill 1996 world champion on BBC Radio 5 Sports Extra in Monaco
Lewis Hamilton has looked quite happy with his car and it seems to be reasonably competitive, he's saying positive things. He's got a bit more of a spring in his step after Imola.
McLaren back in the mixpublished at 15:12 British Summer Time
15:12 BST
Oscar Piastri was on pole position in Imola and he's 13 points clear in the drivers' championship. The Australian can't quite overcome his McLaren team-mate Lando Norris just yet - the Briton has just gone quickest again - but the papaya cars are mixing it with the Charles Leclerc and Max Verstappen.
Pierre Gasly is fuming as the Aston Martin of Lance Stroll gets in the Alpine driver's way.
There can even be jeopardy for the front runners in this first part of qualifying because the track evolution is so high. You can do a lap and think it's OK, but if the track evolution is more than you expect grip ramps up quickly at Monaco when you've got 20 cars going around absolutely on the limit.