Mercedes Motorsport boss Toto Wolff has said the "qualities" shown by the three-time defending world champions in their battle with Ferrari have most impressed him this season.

The German manufacturer lost their status as the sole dominant team in Formula 1 this year, as Ferrari used significant aerodynamic changes to close up on the Brackley-based team, whose own car admittedly fell short of expectations.

Gradually, Mercedes has been making progress and appear to have mostly overcome tyre problems that were most prevalent in Monaco, carving a strong development path which looked to be moving them ahead of their Italian rivals, until they fought back with a 1-2 in Hungary, regardless, the response to their new fight is what Wolff most highlighted reflected on the year-to-date.

“The summer shutdown came at the perfect time for us to make a step back and take stock of our season so far. It has been a good one - and has shown a lot of the qualities of our team,” he claimed.

“We have overcome a difficult start to testing and significantly improved a fast but tricky car; we have won six races from 11, including victories for both our drivers.

“We trail in one championship by 14 points and lead the other by 39, but it hasn't been easy sailing. We have learned hard lessons, grown strong as a group and there are still many areas for us to keep improving.”

Though the challenge from Ferrari this season surprised many, Wolff believes it was the anticipation of a new threat as well as not resting on laurels that led to Mercedes maintaining their status as one of, if not, the best team on the grid.

“It was clear to all of us that 2017 would be a very different season to the three that came before,” he said. “Then, we had the luxury of a performance advantage to the rest of the field, which meant our two drivers were fighting for the title between themselves.

“For this year, the rules were changed to reset the competitive balance across the field and it worked (but), for the first time ever, the champion team has maintained its status as a pacesetter after a big rule change and we are proud that we laid down that marker.

“But that is now history, we have been joined by Ferrari and also Red Bull as the season has developed. This is the new reality we are racing in now and we are open-minded enough to adapt our approach to those new circumstances.”

Looking ahead to the Belgian Grand Prix, that will begin the final run-in to Abu Dhabi in November, many believe the power requirement at Spa will suit Mercedes, as it has at similar circuits so far, but Wolff played down such claims.

“On paper, people will assume that Spa should suit our car because it is a circuit where aerodynamic efficiency is extremely important,” he said. “But assumptions are dangerous. We have seen too many times already this season that the form book can be rewritten from one weekend to the next.

“So we will be making no assumptions; we have to tick off the items on our work list and make sure we do the best job to maximise our potential points score."