The air conditioning in the Toyota Corolla was working overtime on the way to the circuit this morning as, despite the cloud cover, the temperature gauge was edging past 30 degrees.

Also working overtime was the local police force with cars at every junction and, once I was nearer the circuit, groups of cars at check points every 100 metres. The police presence this morning was the first and only sign for many that all is not well in Bahrain.

Once inside the circuit’s confines there was business as usual with first and second practice. We don’t know what fuel loads all the cars were running, but it looks like Ferrari, Red Bull and Lotus all look strong in race trim.

It hasn’t been easy for teams to get a handle on potential set ups, however, because of the changing nature of the track. The dusty sand that blows off the surrounding desert means that the circuit vastly improves over the course of each session as more cars lay rubber down and clean the Tarmac. It doesn’t necessarily continue to improve, though.

“Generally I believe that the track evolves until the end of the day,” said Hamilton after finishing 10th in the second practice session. “In the night it drops off again and then the next day it’s a bit better. It then drops off again in the evening. It’ll get better again through the race, but it’s not just a constant evolution throughout the weekend.”

Hamilton admitted that he had a long night ahead trying to find a better balance with the Mercedes, but also having a long night will be Sergio Pérez. The Mexican has had a mixed start to his McLaren career. He’s scored just two points – in Malaysia when Button had a wheel problem – and it has since been suggested by team principal Martin Whitmarsh that he needs to improve. While Pérez believes the performances in Australia and Malaysia were good considering the car’s lack of pace, he does admit that last weekend’s Chinese Grand Prix was difficult.

Whitmarsh has since said that he needs to be more aggressive – not easy when you’re constantly being told that you have to conserve your tyres during the race.

“We had a word about it,” said Pérez regarding Whitmarsh’s comments, “and it’s difficult to judge when you can be aggressive and when you can’t. When you are on a different strategy and you are mainly looking after your tyres the worst thing you can do is to fight someone next to you that is on a different strategy and is three seconds faster than you. You may not be fighting that guy; you might be fighting someone behind that.

“I’m definitely feeling the pressure. At McLaren everyone is watching your performance in every single practice and in every single race. I find it quite amazing that after three weekends, when two of those were good in terms of maximising the car’s potential, I receive so much criticism. I think it’s maybe quite normal for a team like McLaren.”

Many claimed that it should have been Hülkenberg taking over Hamilton’s seat at McLaren this year rather than Pérez who, despite two podiums aboard the Sauber in 2012, struggled to match the German’s eye-catching performances in the Force India. A statistic that Pérez no doubt won’t want to hear is that since the start of the Brazilian race last year it is Hülkenberg that has led the most laps out of the entire grid…

While the world took notice of his great performances at the 2012 Malaysian and Canadian Grands Prix, at McLaren the world will take notice anytime that he’s not as fast as he should be. It’s difficult for him to shine in a car that’s not worthy of podiums on pace alone, but he’s going to need a strong performance this weekend to quickly dispel any questions over whether he should be at McLaren or not.

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