Malaysian Grand Prix 2015: 5 Key Storylines Ahead of Sepang Race

After an underwhelming start to the season Down Under, the Formula One circus reconvenes this weekend outside Kuala Lumpur for the Malaysian Grand Prix.

The Sepang International Circuit was the first track Hermann Tilke designed from scratch, and it remains one of his best. The two long straights connected by a slow hairpin remain the circuit's defining feature, but it also offers a challenging array of high- and medium-speed corners.

But aside from the track—and its inevitably unpredictable weather—this weekend features several developing storylines, from the return of a champion to the breakdown of the Red Bull-Renault relationship.

Here are the stories you should be keeping an eye on this weekend in Malaysia.

Red Bull and Renault's War of Words

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Cyril Abiteboul and Christian Horner

Last season, Red Bull won three races with Renault engines and, in the four years before that, the same partnership produced four drivers' and four constructors' titles. Now, after one year and one race, the Red Bull-Renault alliance is on the rocks.

Complaints from the Red Bull side of the garage began mid-way through the 2014 season and have only grown louder as problems persisted in preseason testing, culminating with the team's disappointing result in Australia two weeks ago.

In Melbourne, per Sky Sports' Mike Wise and James Galloway, team principal Christian Horner complained, "It’s frustrating that we’re effectively even further back than we were in Abu Dhabi in both power and driveability.

"Ferrari have made a good step. Renault, at this stage, appear to have made a retrograde step."

This week, in an interview with French magazine Auto Hebdo (h/t ESPN F1), Renault managing director Cyril Abiteboul called Red Bull designer Adrian Newey a liar after he said, "Renault haven't got it together," among other things, per ESPN F1.

If Red Bull does not have both cars fighting near the top five this weekend—and Renault's power deficit combined with Sepang's long straights suggests they won't—expect more insults to fly. At this point, it may just be a matter of which side decides to end the partnership first.

The Return of the King

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Fernando Alonso in the McLaren garage in Malaysia.

Following an unexplained crash in preseason testing, McLaren's Fernando Alonso missed the opening race in Melbourne as he recovered from a concussion that CEO Ron Dennis originally said he didn't have. McLaren's less-than-forthcoming approach to communications in the aftermath led to a variety of conspiracy theories popping up in the dark corners of the internet, but he is now in Sepang and ready to race, pending an FIA medical test.

Whether the Spaniard actually gets to race is another matter. Kevin Magnussen took over his car in Australia but broke down on his way to the grid, continuing a disastrous beginning to the rekindled McLaren-Honda partnership.

Alonso does not have any illusions about the challenges facing the team, though, saying, "It’s clear we have a lot of work ahead of us but Jenson [Button]’s result in Melbourne was encouraging from the point of view of reliability and data collection," per McLaren's race preview.

If Alonso and Button hope to get anywhere near the points in Malaysia, they will need some serious attrition. On the bright side, Manor should be racing this weekend, so McLaren won't have to worry about qualifying last.

Can Nico Rosberg Respond to Lewis Hamilton's Melbourne Victory?

Associated Press

Lewis Hamilton leads Nico Rosberg at the Australian Grand Prix.

Going back to last season, Lewis Hamilton has won seven of the last eight races. Nico Rosberg needs to reverse that run soon or his confidence—and his championship hopes—could start to ebb.

Hamilton, meanwhile, knows that no lead is safe in the title race. In 2014, Rosberg had a 29-point advantage over his team-mate after the Belgian Grand Prix. Two races later, Hamilton was back in front and he never relinquished the championship lead again.

Last year at Sepang, Hamilton qualified on pole and finished 17 seconds ahead of Rosberg in the race. At the last grand prix, in Melbourne, Rosberg could not get close enough to attempt a pass on Hamilton.

For the sake of the fans, hopefully Rosberg and Hamilton will have another close championship battle this season, but, until Rosberg shows he can repeatedly beat his team-mate in a straight fight on the track, the title is Hamilton's to lose.

The reigning champ certainly isn't lacking for confidence: In Mercedes' race preview, he said, "I feel ready for anything right now."

Are Ferrari for Real?

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Kimi Raikkonen and Sebastian Vettel in Melbourne.

Aside from Mercedes, Ferrari (and their engine customer, Sauber) were the stars of the show in Melbourne. Sebastian Vettel finished on the podium in his first race for the Scuderia and Kimi Raikkonen looked set for a top five finish, too, until a botched pit stop ended his afternoon.

After failing to score in 2014, Sauber had both cars in the points for the first time since the 2013 Japanese Grand Prix. Felipe Nasr was particularly impressive, finishing fifth in his F1 debut.

At Thursday's FIA press conference, Raikkonen said, "The car’s been quick at every circuit we’ve been to so far so I don’t see any reason why it shouldn’t be here. I think it could be even better than it was at the last race."

Vettel sounded even more confident, saying, "We must attack and try and close the gap to Mercedes and with the conditions you can get here, a win is always possible," per a team press release.

With Red Bull struggling, it will fall to Ferrari and Williams to try to push Mercedes—and perhaps pick up the scraps if the Silver Arrows run into trouble.

Race Strategy and Tyre Choice

Dita Alangkara/Associated Press

The probability of rain is always high at Sepang.

Most drivers only made one pit stop in Australia, aided by a relatively smooth track surface and an early safety car. This limited the opportunities for race strategies to play a significant role in the race.

In Malaysia, with a high-degradation circuit, several fast corners, high temperatures and the ever-present threat of rain—the BBC's current forecast for Kuala Lumpur calls for rain on all three days—strategy and tyre choice will play a much larger role this weekend.

Pirelli are bringing medium- and hard-compound tyres to Sepang, but even so, motorsport director Paul Hembery thinks, "We should see a return to at least two stops per car in Malaysia—perhaps more if the weather gets in the way," according to the tyre company's race preview.

Last year, the Mercs three-stopped to a one-two finish. This year, rain on race day would give the other teams the best chance to stop another Silver Arrows sweep.

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