BARCELONA, Spain -- After doing back to back tests in Barcelona on Tuesday, Sebastian Vettel says Pirelli was right to bring thinner tread tyres to the Spanish Grand Prix last weekend.

After Mercedes outpaced Ferrari throughout the race weekend in Spain there were suggestions that Pirelli's decision to bring thinner tread tyres gave a benefit to Mercedes. The decision was based examples of overheating and blistering at the same circuit during pre-season testing, which was partly due to a lack of wear on the new, smooth track surface, which was relaid over the winter.

The more rubber on the tyre, the more heat it retains -- and without the normal level of wear the surface of the tyre was getting so hot through Barcelona's high-speed corners that it started to blister. In agreement with the FIA, a decision was made to reduce the thickness of the tyres by 0.4mm for the Spanish, French and British Grands Prix in an attempt to avoid a repeat in the races.

As part of Ferrari's investigations into its lack of race pace on Tuesday, Vettel tested standard tread versions of the soft and medium compounds as well as thin tread tyres in a back to back comparisons. The thick tread tyres came back with obvious signs of overheating and Vettel admitted after the session that they would have exacerbated Ferrari's issues if they had been used on Sunday.

Sebastian Vettel tested Pirelli's normal tyres on Tuesday and had even more issues than he had on Sunday. David Ramos/Getty Images

"I think it's pretty straightforward," he said. "Obviously you don't get the chance to revisit this kind of decisions that are made [very often], but we did it today and the result is that if we had had the normal tyres on Sunday, it would have probably been worse, so it was the correct call. It was our fault for not having the same tyre wear or life as other people."

Vettel said Ferrari used Tuesday's test to work on improvements in an attempt to solve the issues it faced over the Spanish Grand Prix weekend.

"It's good to have the test to be able to compare and I think we have some ideas. Now it's up to us to turn those ideas into reality. As I said it was good in terms of timing, coming from a poor weekend for us, we were not quick enough and more than not being quick enough we were struggling to make the tyres last -- these things have a link -- so it was good to have a possibility to revisit it and now it's up to us to take action.

"Obviously it looked like from the outside they [Mercedes] had a stronger weekend, without any big issues, but we need to look at ourselves, focus on our car and our problems, so we'll be stronger again."