Ferrari claimed first and third position on the timesheets in the final hour of free practice ahead of qualifying for the Monaco Grand Prix, but the session was overshadowed by major accidents for both Tonio Liuzzi and, more significantly, Nico Rosberg.
Picking up from where he had left off on Thursday, Alonso used the supersoft Pirelli to lower the weekend's benchmark time to 1min 14.433secs, ending the interrupted 60 minutes more than half a second clear of his nearest rival. The Scuderia, looking to bounce back from a Spanish GP which promised much but yielded little, was also boosted by Felipe Massa's run to third spot, the Brazilian only marginally slower than McLaren's Jenson Button, who took second place.
For the second session in succession, points leaders Red Bull Racing failed to appear in the top three, but world champion Sebastian Vettel was fourth fastest as pit-lane fingers began pointing at a possible case of sand-bagging from the sport's number one pairing. Vettel ended the morning fully eight-tenths off the pace, but few expect that to be the case when qualifying gets underway.
Vettel was closely followed by fellow German Michael Schumacher, while Lewis Hamilton also squeezed in ahead of the second Red Bull of Mark Webber, the Australian the first of those a second and more off Alonso's time. Hamilton, however, had yet to complete a meaningful run on the supersofts by the time of the second red flag interruption, and may also have more to show on Saturday afternoon.
The rest of the top ten was filled by the unlikely trio of Jaime Alguersuari, Sebastien Buemi and Sergio Perez, despite the Toro Rosso team having to deal with damage from a collision with the barriers. Paul di Resta had filled the final slot prior to the stoppage, but was pipped by Perez as the chequered flag fell.
Williams was boosted by having both Rubens Barrichello and Pastor Maldonado around the mid-point on the timesheets, despite the pair again running different strategies on their rear wing choice. Kamui Kobayashi and Vitaly Petrov rounded out the top 15, with Nick Heidfeld next up on a disappointing morning for Renault, which took a front row spot with Robert Kubica twelve months ago.
Also missing from the leading group was the Mercedes of Rosberg, which halted the session almost as soon as it had started after hitting the barriers hard on the exit of the tunnel. Similar to several of his rivals, the German had his car snap sideways of the bumps exiting the famous landmark, but the right rear caught the barrier hard and succeeded only in pitching the front corner into the armco as well. Rosberg continued at barely unabated speed into the run-off-area, narrowly missing the end of the barrier that left Karl Wendlinger in a coma in 1994, before finally coming to rest on the run to Tabac.
The German was able to climb out of the wreckage unaided, and surveyed the state of his car for some time before it was craned away, while Liuzzi was also fortunate to walk away from a similarly heavy accident at Ste Devote, after his HRT snapped into oversteer as he reached the apex. The entire left-hand side of the Italian's car was heavily damaged and, like Rosberg, he remains a doubt for qualifying.