Mercedes boss Toto Wolff believes the unexpected Ferrari victories this season have acted as a good wake up-call for the team and forced them to make new targets.

The Brackley-based outfit dominated the 2014 campaign with Lewis Hamilton winning the drivers’ championship from team-mate Nico Rosberg.

The Brit finished 67 points ahead of the German while he was a massive 146 ahead of Red Bull’s Australian star Daniel Ricciardo in third position.

Much of the same was expected in the current season and it looked like it was going to be another easy road to success after the defending champion won in Australia on race weekend one with his team-mate taking second place.

However, Sebastian Vettel, who moved to Ferrari from Red Bull at the end of the previous campaign, managed to take top spot in Malaysia from Hamilton.

The four-time world champion also won in Hungary last time out and the Maranello-based outfit have added some strong competition to the Mercedes pair.

Wolff believes the Ferrari resurgence has helped the team and says the victories have acted as motivation to everyone involved.

“Malaysia was certainly a little bit of a wake-up call,” he told Motorsport.com “After Melbourne we felt we had the situation under control and we were caught out for various reasons. And in hindsight, maybe such a little slap is good sometimes for the organisation.

“We have definitely benefited because we have probably set new, more aggressive targets in terms of development, lap time targets and quality expectations. We know that the threat is real.”

Hamilton is favourite at 1.53 to win the next Grand Prix in Belgium on August 23 while Vettel is priced at 8.00 to cause another upset.