Fernando Alonso dominated the opening day of practice at the 68th Monaco Grand Prix yesterday when he topped the times for Ferrari in both the morning and afternoon sessions run in variable conditions.

After clocking the fastest time in a closely-contested morning free practice, Alonso cut a second off his best lap time in the afternoon when the sun shone briefly, the 28-year-old Spaniard delivering a best lap in one minute and 14.904 seconds round the famous old street circuit.

On a day when the teams spent as much time with a wary eye on the sky and tried to second-guess the capricious Monaco micro-climate, the two-time champion was at his supreme best as Ferrari set about the pursuit of their first win in the Mediterranean principality since Michael Schumacher's victory for them in 2001.

That was the fifth and final triumph at this venue by the now-41-year-old veteran, making his comeback this year with Mercedes after retiring prematurely three years ago as a seven-time champion.

Schumacher wound up down in fifth place behind a top four made up of the smooth, near-flawless Alonso, who was one-tenth of a second ahead of German Nico Rosberg, in the leading Mercedes, German heir-apparent Sebastian Vettel, of Red Bull, and Brazilian Felipe Massa in the second Ferrari.

Schumacher was fifth, but after a scruffy session that included almost colliding with defending champion Briton Jenson Button's McLaren in the pit lane and a near-scrape of the barriers at Portier and then an excursion across the chicane at the exit of the tunnel.