SHANGHAI (AP) — When the Formula One season resumes at this weekend's Chinese Grand Prix, the biggest battles will be between sets of warring teammates rather than rival teams.
The division is deepest at Red Bull where — three weeks on from the Malaysian Grand Prix — there is still plenty of ill-feeling between three-time world champion Sebastian Vettel and No.2 driver Mark Webber following the events of Sepang, where the German ignored team orders to stay behind Webber and instead overtook the Australian and claimed the race win.
The fury in the immediate aftermath — reports that Webber would walk out on the team, that Red Bull must suspend Vettel — has died down in the weeks since due to the German's public contrition, but has not gone away entirely.
"He's said he can't turn back the clock but he's accepted what he did was wrong," team principal Christian Horner said of Vettel.
"He's apologized to the team and to every single member of staff for his actions, because he recognizes the team is vitally important and being part of the team is a crucial aspect to being able to challenge for those championships."
Horner, whose own authority was undermined by Vettel's actions because it was his order that was ignored, once again finds himself having to placate an understandably angry Webber.
The events at Sepang represented the deepest fissure yet between the two Red Bull drivers, trumping 2010 when they collided on track at the Turkish Grand Prix and then at the British Grand Prix the same year Webber was forced to use an old front wing because his new one was handed to Vettel, but went on to win the race anyway.
Webber had returned to Australia in the weeks since Malaysia to mull over his future, but Horner was sure he would see out the remainder of his one-year contract.
"He is big enough to know there was no malice and no intent to create any situation like that. He is in a car capable of winning grands prix and hopefully winning world championships," Horner said of Webber on Sky Sports.
"I have no doubt Mark will see out the contract with us."
The conflict at Red Bull meant the other team orders conflict from Sepang was largely overlooked, with Mercedes telling Nico Rosberg not to overtake third-placed Lewis Hamilton despite the German's protestations he was the faster car.
Heading into this Sunday's race in Shanghai — where Hamilton is the only two-time winner and Rosberg the defending champion — team boss Ross Brawn had denied the team orders indicated Hamilton was the de facto No.1 driver in the team or that he was given any such promise when making the move from McLaren.
"In the contractual negotiations we had with Lewis, never was the issue of who was number one or number two ever mentioned from his side," Brawn said.
"He wants the same equipment, the same opportunity and that is great that he has that confidence and that approach that he doesn't want favoritism, he just wants parity and that is why Lewis felt a little bit awkward about the situation."
The other intriguing teammate fight is at Ferrari, where a revived Felipe Massa is sustaining his challenge to the undisputed No.1 Fernando Alonso.
Massa has qualified ahead of Alonso in the past four races: the United States and Brazil at the end of 2012 and now Australia and Malaysia this season. Should he do so again in China, it will be the first time in Alonso's F1 career that he had been out-qualified by a teammate five times running.
Alonso, though, had usually got the better of his teammate on race day, and will be aiming for another strong performance in China to make up for his non-finish in Malaysia, with expectations high of a title challenge this season.
Another team badly needing an improved performance is McLaren, which was well off the pace in the opening two races as looks to remedy the teething problems of its new-look 2013 car.
The three-week break between Malaysia and China came at the right time for McLaren, which believes it will produce a car in China which is more consistent in its performance across various levels of fuel load and tire degradation.
"The engineers, designers and mechanics, too, have worked tirelessly and painstakingly to unlock the car's potential, and we feel confident that we are starting to turn the page," team principal Martin Whitmarsh said.