Ahead of today's opening practice session the air temperature is 17 degrees C, while the track temperature is 24 degrees. It is what Marussia earlier described as "moist", a light drizzle having been falling throughout the morning. However, as the session is about to get underway the sun is shining and the track is dry. Though there is only a 20 percent chance of rain, teams and drivers appear to feel the chances are higher.

Tyre choices this weekend are the same as in Canada, soft and supersoft, whilst there are be two DRS zones with both sharing a single detection point, located 110m after Turn 9. The first activation point is 55m before Turn 12, the second 70m after Turn 14.

Just one reserve driver on duty today, Alexander Rossi replacing Kamui Kobayashi in the Caterham.

Massa leads the way when the lights go green, followed by Magnussen, Kvyat, Bianchi, Vergne and Gutierrez. Rosberg, another early riser, has a camera fitted to the rear wing. Talking of rear wings, the back end of Raikkonen's car is yellow such is the amount of flo-vis the F14T is sporting.

Soon all have been out, including those drivers usually a little more shy when it comes to Friday mornings. A number complete two laps but no times.

Thirteen minutes into the session Magnussen is the first driver out for a second run, the Dane having said earlier this week that the double podium finish in Melbourne was the worst thing that could have happened having given his Woking team false hope.

Magnussen posts the first time of the day, the Dane stopping the clock at 1:23.249. Next time around he raises the bar with a 21.061.

As Maldonado gets the T9 chicane all wrong, teammate Grosjean posts 22.504 to go second.

As Magnussen and Grosjean trade best times, Rosberg goes seventh with a 25.921. He subsequently improves with a 20.060 as Massa raises the bar with a 19.575.

A spin at T9 for Hulkenberg sees a Williams have to take avoiding action as Ricciardo appears to brush the wall. Hulkenberg admits to having "touched the grass" under braking.

Having posted the best time thus far (18.997), Hamilton subsequently gets it all wrong exiting T2.

The greenness of the track means we are going to see lots of mistakes today, particularly in this session.

As Hamilton looks set to improve, Alonso takes a rough ride over the kerbs and teammate Raikkonen complains of having lost power. "We heard some knocking," is the response.

Just twenty-eight minutes into the session all but Gutierrez have posted a time, Hamilton heads Rosberg, Alonso, Perez and Hulkenberg.

After half-an-hour, with the extra set of tyres for FP1 running handed back, silence descends on the Circuit Gilles Villeneuve.

In the Ferrari garage there is frantic activity on Raikkonen's car following that earlier knocking sound. Meanwhile, in the Mercedes garage, the floor has been removed from Rosberg's car.

After around ten minutes of inactivity Magnussen and Kvyat head down the pitlane.

The Russian is clearly struggling. Having hit the kerbs at T1 hard he subsequently runs wide in T8.

Maldonado runs wide at T10 and Ericsson at T8 as Rossi is informed that his tyre temperatures are "at the bottom" of their working range.