Where does Rosberg go from here?

How long before a fluke becomes a pattern, or a pattern becomes a trend? Not every driver is fortunate enough to drive the best car in Formula 1 for a single season, let alone two, but Nico Rosberg has been that fortunate - just not fortunate enough to convert that opportunity into a world championship victory.

For the second season in a row Rosberg finds himself vanquished by Mercedes team-mate Lewis Hamilton, this time far earlier and far more convincingly than in 2014.

Last year Rosberg could, rightly or wrongly, boil his loss down to chance. Everything rested on the double-points finale in Abu Dhabi. Rosberg qualified on pole position, but the car let him down. Hamilton won the championship. Simple.

Except deep down Rosberg knew he didn't lose the title in Abu Dhabi; he lost it gradually, when his car failed before the start in Singapore, when he was overtaken by Hamilton for victory in Japan and the US, when he made mistakes while in potentially winning positions in Italy and Russia.

Rosberg's determination to come back better and stronger this year was admirable, but it hasn't paid off. Whatever improvements he made over the winter were not enough. After winning five races and taking the title fight all the way to the final race in 2014, this year Rosberg found himself comfortably defeated with three races still to run and fighting just to be runner-up in the standings.

The internal inquest will already have started. And it will no doubt be more painful than last year's. Rosberg's next moves could be crucial in shaping his future as a Formula 1 driver, so how he proceeds into 2016 and beyond requires careful consideration.

CHALK IT UP TO BAD LUCK (AGAIN)

Rosberg has suffered some bad luck this year, firstly at Monza where Mercedes introduced an upgraded engine that had to be replaced on Rosberg's car when some coolant contaminated the power unit during free practice.

That meant he had to revert to an older, less powerful and more tired engine, which then failed in the race as Rosberg attempted to catch Sebastian Vettel's Ferrari for second place.

He lost 15 points there, and a likely maximum score of 25 at Sochi, where his throttle stuck open and forced him into retirement.

That bad fortune has ultimately ended his title hopes a little earlier than expected, but isn't the main reason he's lost the championship.

If the title race had been closer to begin with, those failures could have proved pivotal, and Rosberg could also have pointed to the compromise of needing to eke out the mileage of his fourth engine over the final seven races of the campaign as significantly detrimental to his chances.

But in truth, such has been Hamilton's superiority this season, Rosberg cannot point to bad luck as the main reason he lost the world championship to his team-mate again. He must simply do better. The question is how?

RE-FOCUS ON QUALIFYING

This is the key area Rosberg needs to address in his personal duel with Hamilton. Last season Rosberg was supreme on Saturdays, scoring 11 pole positions, and winning the FIA's inaugural pole position trophy for the driver with the most across the season.

This year Rosberg has managed to take pole just five times in the 18 races held so far, which is a key aspect of his early defeat in the 2015 title race. Rosberg likes to suggest that the difference between himself and Hamilton is all about small margins and that "if it doesn't tip in my direction, it's done".

But in actual fact that's only really been the case at Shanghai, Silverstone and Singapore, where in each case Rosberg qualified within 0.130 per cent of Hamilton. Otherwise, the deficit has been substantially larger.

Of the five pole positions Rosberg has secured this year, three (Spain, Russia and Mexico) were by a large margin. The rest of time Hamilton has lapped within 0.1 per cent of his team-mate.

Rosberg has been 0.197 per cent slower than Hamilton on average in qualifying this year, across 16 races (Monza is disregarded on account of the two drivers using different engine specifications). Last year, Rosberg was 0.164 per cent faster than Hamilton across the balance of the season (Germany and Hungary are disregarded on account of technical problems for Hamilton).

That seems like a massive swing from one season to the next. But if you take out two massive outliers in the 2014 data, China (where Rosberg spun on his final Q3 attempt, favouring Hamilton) and Silverstone (where Hamilton bizarrely aborted his last Q3 run in the rain, favouring Rosberg), the gap was only 0.019 per cent in favour of Rosberg.

So although Hamilton appeared to have been trounced by Rosberg in qualifying across the balance of last season, in actual fact he only needed to find a small amount of extra performance to gain the upper hand. This is probably why Hamilton has been able to improve in qualifying this year, without sacrificing his race speed.

The workload Rosberg faces in trying to regain the qualifying advantage is much greater than Hamilton faced heading into the winter of 2014. Rosberg has spoken of adjusting his approach to set-up (generally dialling in more understeer to protect the rear tyres) in favour of the races this year, but whatever tweaks he made have come at too heavy a price on Saturdays.

Back to the drawing board he must go, though he can at least draw some encouragement from a recent run of four poles in the past four races. Perhaps that homework has already begun...

EMPHASISE THE POSITIVES

This year is not all doom and gloom for Rosberg, even though he came nowhere near winning the championship, and so far has won fewer races than he managed in 2014.

The manner of his victory in Austria this year, where he overtook Hamilton at the start and beat him fair and square for pace in a straight fight, demonstrated the fact that he is capable of beating his rival without the aid of some mechanical misfortune or incident, which happened regularly in 2014.

His performance in winning the recent Mexican GP was also exemplary, proving that he can put a whole grand prix weekend together and close out victory with Hamilton snapping at his heels all the way through.

He also seems to have a small edge in changeable conditions, such as those seen in the closing stages in Britain and early on in the recent United States Grand Prix. On both occasions Rosberg was faster than Hamilton during the phase of those races where track conditions were changing fast, and the tyres were not ideal for coping. Whatever aces Rosberg has up his sleeves in these circumstances, he needs to hold onto them tightly.

The way he charged back into the lead at Austin, after dropping to fifth on the opening lap, also shows that Rosberg doesn't lack fight, or the ability to get his races back on track when things go against him.

He will need to harness a lot more of this kind of determination, and an ability to reset mentally, if he is to beat Hamilton regularly in the future.

CONQUER THE WHEEL-TO-WHEEL CONUNDRUM

Apart from the qualifying reversal, this is probably the biggest problem Rosberg must address if he is to get on terms with his triple-champion team-mate.

It all began in Bahrain in 2014, when Rosberg qualified on pole and was faster than Hamilton in the race, but simply could not make a passing move stick to get back into the lead.

Every time he tried, Hamilton found a way to strike straight back and reclaim the advantage of track positioning. There was one moment in particular, where they came out of Turn 4 together and headed into the fast chicane of 5/6 side-by-side, in which Hamilton forced Rosberg to either back out or risk collision. Rosberg backed out, and from then on, Hamilton has held the psychological edge in combat.

Spa 2014, where Mercedes severely reprimanded Rosberg for driving into Hamilton at Les Combes on the first lap, further deepened this distinction. Rosberg was desperate to prove he was no pushover in wheel-to-wheel battle, but ended up damaging two cars and his own relationship with the team.

This must have been music to the ears of Hamilton, who looked a bit concerned by Mercedes' reaction to incidents earlier in the year, involving engine maps and one particular qualifying controversy in Monaco.

It is in this context we must place key incidents at Suzuka and Austin this season, where Rosberg and Hamilton again went wheel-to-wheel and each time Hamilton was able to aggressively force his team-mate to back out, or risk a collision. In America, they had that collision, and it was psychologically important for Rosberg that they did.

You can argue that Rosberg was slow off the line and perhaps should have conceded the corner, but Hamilton was not ahead when they reached the braking zone, and conceding would only have added more ammunition to Hamilton's psychological armoury.

Looking at how deep both cars went into Turn 1 at Austin, it's clear Hamilton wasn't trying to give his team-mate racing room; he was taking the lead come what may, and daring Rosberg to challenge that authority.

Rosberg was unable to stay ahead, but the important thing is that he didn't yield. The cars collided and he came off worse - this time...

Mercedes was not overly impressed with what happened in America, calling the incident "a hard move" on Hamilton's part, and relations between the two drivers have again descended to sub-zero levels.

But Hamilton is an extraordinary driver, so it's crucial for Rosberg's personal ambitions that he continues to go hard at his team-mate, and be prepared to endure more potential Spa 2014s and Austin 2015s.

This is a hard game, after all, and there is no time for niceties when the ultimate prize is on the line. Rosberg needs to be tough, and prove that Hamilton hasn't got him covered when they race wheel-to-wheel.

FACE THE INFERIORITY COMPLEX

Of course we know that certain teams throughout the history of Formula 1 have given certain drivers contractual 'number one' status, making it a near-impossibility for their team-mate to beat them.

That's not the case at Mercedes, which regularly talks of the importance - for the spectacle of F1 - of letting its drivers battle it out on an equal footing, especially while its car remains the dominant package on the grid.

But a natural dynamic can still emerge over the course of time, especially if one driver regularly beats the other, and there is now an argument to suggest that dynamic could start to emerge at Mercedes.

2013
Hamilton: 1 win, 5 podiums, 5 poles, 189 points (4th in the championship)
Rosberg: 2 wins, 4 podiums, 3 poles, 171 points (6th in the championship)

2014
Hamilton: 11 wins, 16 podiums, 7 poles, 384 points (1st in the championship)
Rosberg: 5 wins, 15 podiums, 11 poles, 317 points (2nd in the championship)

2015
Hamilton: 10 wins, 15 podiums, 11 poles, 384 points (1st in the championship)
Rosberg: 4 wins, 14 podiums, 5 poles, 317 points (2nd in the championship)

2013-2015
Hamilton: 22 wins, 36 podiums, 23 poles, 818 points, 2 world titles
Rosberg: 11 wins, 33 podiums, 19 poles, 760 points, 0 world titles

Hamilton is arguably the natural number one driver at Mercedes already, just by the very fact of his continued success against Rosberg.

This is his third season at the team (Rosberg has been there since 2010), he clearly feels more comfortable with each passing year, and the more he asserts himself as the better driver, the more influence he is likely to wield within. It is not an active or conscious process; it is just the way of the world.

Mercedes will of course continue to treat its drivers equally (except perhaps if one ends up embroiled in a title fight with a rival from another team with the other not in contention), but natural harmony is difficult to maintain without one driver becoming submissive.

With Hamilton and Vettel potentially emerging as natural number ones in two competitive teams, perhaps Rosberg needs to face the fact of potentially becoming de facto number two at Mercedes. Unless he can reverse the tide.

Rosberg stands at an important career crossroads here. If he cannot find a way to beat Hamilton over a season, he may have to face the possibility that he will never do so while they are team-mates.

If he manages to beat Hamilton in the same team it's unlikely they could remain team-mates for too much longer anyway, as history shows there is not usually enough room for two roosters in the henhouse.

If Rosberg cannot become Mercedes' 'alpha male', perhaps he needs to search for a new home? One where he can establish himself as the undisputed leader, and take Hamilton on from afar without the potentially suffocating pressure of responsibility to a shared corporate identity.

Rosberg's current Mercedes deal expires at the end of next year. He remains a very fine grand prix driver at present, but what he does over the next 12 months could make or break his ultimate destiny in Formula 1.