Mercedes may need to change line-up - Webber

Mark Webber believes Mercedes has a big decision to make whether it sticks with Nico Rosberg and Lewis Hamilton as its driver line-up for 2015.

Hamilton and Rosberg's partnership was strained even further when the two collided in the Belgian Grand Prix, with Hamilton claiming after the race that Rosberg had admitted he chose not to avoid the incident. Rosberg recently signed a new contract at Mercedes and Hamilton's current deal doesn't expire until the end of 2015, but Webber believes there's a chance the team will have to allow one of them to leave at the end of the season.

"It's going to be interesting, not just for the rest of the year," Webber told Sport und Talk. "At the moment it's not a team. Is it OK to have them together in 2015?

"It looks like the drivers are doing their own thing. Can they drive together in the future?"

While Webber doesn't believe Red Bull's Daniel Ricciardo has a realistic chance of winning this year's title - saying "Mercedes will really need to implode for Daniel to take the championship" - he does feel neither Hamilton nor Rosberg will be wary of an outside challenger.

"Let me tell you, when they get to the track, they'll only be thinking about each other. There's no-one else really in the race. They are really only focused on beating each other and that's what happens when you have a car that is so dominant.

"They are going to win the constructors' [title] easy, so the drivers know that the constructors' is done, so all that's left is the drivers' championship."