Lotus technical director Nick Chester is delighted following the E23's first test, the new relationship with Mercedes being "brilliant".

While the team missed the first day of the test, it soon made up for it. Over the three remaining days, Pastor Maldonado and Romain Grosjean completed 190 laps, more than Red Bull and McLaren.

"Obviously we missed the first day's running and had a big push to ensure that we could get running on the second day which was actually earlier than we expected," says Chester. "Straight away the car was good out of the box, very reliable. We found working with HPP has been brilliant, it's a very easy relationship. The performance is coming along nicely too. It's been a very good test for us.

"The objective was to get some mileage and flush out some of the major problems we might encounter so that we could go to Barcelona knowing that we had a reliable car," he continued. "We've definitely done that and more. We've been able to do a little bit of set up work and start understanding the car.

"In terms of reliability, we have suffered from very little," he revealed, "a few wiring problems, a few software problems and one small detail design problem so it's actually been pretty easy. Generally the car has worked very well."

Asked how the drivers have reacted to the car, he says: "They find it massively easier. The objective was to have a car that was easier to work with than last year's and it is. It's like night and day so far.

"They're very positive, they both find the car a lot more consistent to drive, they love the power unit which is very flexible for them and the whole package is much easier for them to drive and put on the limit."

Looking ahead to the tests at Barcelona.

"We will focus a lot more on set up work, understanding the car and getting the best out of it. We will also have new aero parts to put on the car as we head towards a Melbourne package. We will also complete the normal long-distance programmes, all the race procedures and getting ourselves fully prepped for Australia."

And before then?

"We will carry out some checks on the car and look at areas we want to improve, and then it will get built to Barcelona spec. There should be a few updates already going on it for the first of the two Barcelona tests.

"Chassis 03 is already built and homologated, which is great," he adds. "We may bring it to the second Barcelona test."