Michael Schumacher believes Saturday's final practice has become all the more important after Friday's sessions were a near washout at Spa.
Despite the best efforts from the drivers on Friday there were long periods during the practice sessions where there was just no action due to the deluge of water pouring down on the track.
Aside from the usual aquaplaning on standing water that drivers have to contend with in a wet session there were also rivers forming across the track making it undrivable.
One man who tried his best was Schumacher who, until the final few minutes of FP2, had been the busiest driver with four laps under his belt.
But even the six-time Belgian GP winner, who is marking his 300th grand prix in Belgium this weekend, couldn't cope with the conditions.
"Coming to Spa this year is very special for me, especially with the honour of being awarded the honorary citizenship of Spa on Thursday, and I look forward to a stunning race weekend.
"Unfortunately the weather today did not allow us to do much more than just basic work as there was too much rain coming down in both sessions.
"There was a lot of aquaplaning, even when just cautiously cruising around the circuit which sometimes you did not see or expect at all, so proper driving was not possible."
Schumacher, though, reckons the lack of running won't have too big of an impact on the rest of the weekend.
"We have a lot of basic data from Spa and we know what to expect.
"Tomorrow's practice will nevertheless be very important, especially as the weather is supposed to be much better. I look forward to going out on this beautiful track again tomorrow."