Kevin Magnussen says Renault have managed to "make the car worse" during the post Spanish Grand Prix test, after he struggled for grip and balance during practice for the Monaco GP on Thursday.
Magnussen ended up three-seconds off the lead pace after crashing into the barriers and although he was running the quicker Renault engine, he says the team have gone backwards with the chassis.
"We have made the car worse and that's a mistake for us because we thought we had made the car better in the test," he said on Thursday afternoon.
"I'm sure some of the things we tried were improvements, but balance wise and set-up wise we have not made the car better for this track."
Magnussen praised the engine side of things, but doesn't believe it makes much difference to where they are.
"It's the chassis," he added. "The engine delivered and it's a good step, but for us we could have the best engine on the grid right now and we'd still be close to where we are."
Speaking of his crash, Magnussen blamed a lack of grip rather than a driving error: "I just understeered into the wall, really. I had no grip. Looking at the data, I didn't go any faster than the lap before, but I turned and I had no grip.
"I hit the wall slightly but it only damaged the front wing, the suspension is okay, so the mechanics won't have a long night."
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