Valtteri Bottas says Williams "needs to stop making mistakes" if it is going to beat Force India to fourth in the constructors' championship.
Force India finished fourth and fifth in the Belgian Grand Prix to leapfrog Williams in the constructors' standings, with Bottas finishing eighth and team-mate Felipe Massa tenth.
Bottas had been running fourth before a safety car period due to Kevin Magnussen's heavy crash. The accident heavily damaged the tyre barrier and Williams was expecting a red flag but opted to pit Bottas after one lap, costing him track position when the red flag came out two laps later.
"They explained to me afterwards they were absolutely sure there was going to be a red flag, so by staying out I would have kept my position, but I think it was just too big a risk to take at that point," Bottas said.
"I was in a very good position, there was no need to risk, in my opinion. We will talk about it more and analyse it well but it was very disappointing. I was in a very good position, the pace wasn’t too bad so we definitively lost a lot of points because of that."
Having followed Sebastian Vettel for a spell through the field after the race was restarted, Bottas says the pace of the car was good but the strategic error proved costly.
"I think it was more or less what we expected! What we saw on Friday was a very strong pace. It was a bit cooler today and I think that helped us. It was quite a positive day in terms of the race pace, but, in the end, we wasted a good opportunity today, now Force India is ahead and if we really want to beat them we need to stop making mistakes."
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