Current championship leader Sebastian Vettel has called upon his former team Red Bull to up its game to make it a three-way fight for the championship this season.
Currently Red Bull's Daniel Ricciardo and Max Verstappen have failed to bother Ferrari and Mercedes, with the two leading teams having won two races apiece this season so far, whilst Verstappen's third place in China is Red Bull's best finish.
Vettel, who won four titles with Red Bull between 2010 and 2014, is confident they will move up the order and establish themselves as a real threat for race wins, particuarly as they are planning to introduce a huge upgrade at the next race in Spain.
"I think it will be a very close race between Mercedes and us, I hope, and I also hope that Red Bull find some pace," he is quoted as saying by Autosport following the Russian Grand Prixi n which he finished second, but extended his championship lead over Lewis Hamilton to 13 points.
"There's a lot of rumours around [regarding the Red Bull upgrade]," he added. "They are a strong team, they know how to build a quick car so I expect it's a question of when rather than if.
"But the sooner, the more exciting it will be for us."
He isn't the only championship contender who has called for Red Bull to join the fight at the front, with Hamilton also believing it would do the sport good.
"Honestly, I hope that Red Bull can improve through the season because I think a third element in the fight, I think would be even more exciting."
