Bruno Senna admitted that a limited number of dry laps had been crucial after his first day as a Renault F1 race driver at Spa.

Putting the arguments surrounding his promotion into a race seat to one side, the Brazilian suffered a tough start to the day when he went off at turn nine in the wet opening session and damaged the rear of his car.

Although there was only limited dry running in the second session before the rain returned, Senna was able to post a best time of 1min 53.835secs and while that was only good enough for 17th place, he said he was pleased with his the day had ended.

"Obviously it was disappointing for my first practice session to be cut short when I slipped off the track, but I was much happier to get a good amount of track time this afternoon," he said. "Despite the difficult conditions, it was much more productive in the second session. I managed to get some dry running too, which was crucial for understanding which direction to go with the car. We also managed to fit in a number of procedures such as pit stop practices and pull aways.

"I'm making up for all these sessions that I've missed in the past by getting more miles on the clock. One thing's for sure - I'm excited about getting back in the car tomorrow."

The opening day of running was also a mixed one for team-mate Vitaly Petrov, with the Russian unable to make the most of the dry track time available after his car developed a steering issue in the second session.

"FP1 was a difficult session with too much water on track, which meant it was difficult to understand how the car's new parts were working," he said. "The grip from the intermediate tyres was okay, both when there was a lot of standing water early on in the session and when the track dried. All in all, it was a normal morning at Spa and we had no problems.

"In the afternoon, we evaluated the setup for intermediate tyres and the car worked well in those conditions. I am happy with the handling of the car and would be quite happy driving it in the same conditions again. When I went out for my first afternoon run on the slick tyres, I felt a problem with the steering in the high speed corners on my first lap. As a result, I returned to the pits so the team could investigate it. The steering did not feel good, so it made sense for me to pit so the team could work on it."