Jenson Button is confident the mistakes McLaren made in Malaysia earlier this year will not be repeated today in Spa.

McLaren foolishly took a gamble with the weather in qualifying at the Sepang circuit, one that badly backfired as Jenson Button and Lewis Hamilton started in season-low positions of 17th and 20th.

As showers fell at the start of the initial 20-minute qualifying session, rather than putting in a banker lap, McLaren waited for the rain to ease.

To their horror it failed to do so, sparking a desperate mad rush for Button and Hamilton to make it into Q2, only for the former to spin into the gravel while the latter lacked the pace required.

After a rain-sodden day at Spa yesterday, and with more wet weather forecast for tomorrow, Button knows what is required on this occasion.

"We won't make the same mistake as in Malaysia. We've learned from that, so we'll see what happens," said Button.

"I thought there would be a bit more sun here than we've had so far as it's the end of August, but the rain gods are upon us.

"If it is wet then it could be complicated and very messy, so we have to make sure in Q1 we are out on the circuit when we need to be at the correct time."

At various stages throughout yesterday's two practice sessions, all drivers used the three sets of tyres available - extremes for bad wet weather, intermediates for damp track conditions and options for when it was dry at the very end of the second session.

After struggling in the last two races in Germany, and especially Hungary four weeks ago, Button emerged from his car far happier than has been the case recently.

"We pretty much endured everything Spa could throw at us," added the reigning world champion who was seventh quickest overall.

"But we got a few laps in and I'm pretty much happy with the way the car feels in every condition, so I'm positive.

"It's just a nice feeling with the car around here, although there are a few areas we need to work on to ensure the tyres are working in their correct state and in certain conditions.

"Although we don't know the pace of others, the important thing is the balance is okay, and I'm happier with the car here than at the last couple of races."

Ferrari's Fernando Alonso was fastest in the wet and dry, proving himself to be a man for all seasons, although he was just as quick to dismiss any significance behind such detail.

"The impression you get on Friday does not always get confirmed on Saturday and Sunday, therefore we have to evaluate today's results with a lot of care," said Alonso.

"The times count for little, or nothing at all, because when the track changes so quickly times can improve or get worse by two or three seconds depending on when you are out on the circuit."

Like McLaren, Ferrari also counted the cost of weather watching in Malaysia as Alonso and Felipe Massa started 19th and 21st.

And like Button, Alonso also knows what course of action to take today should rain dictate matters.

"When thinking about going for pole position, first of all we will have to see what the weather is doing," added Alonso.

"For sure if it was to rain we will go out immediately because you always learn from bad experiences."