5 Things Nico Rosberg Must Do to Close Gap on Mercedes Team-Mate Lewis Hamilton

Nico Rosberg had a good crack at winning the Formula One title in 2014, but his best wasn't quite good enough to topple Lewis Hamilton.

The gulf in class between the Mercedes, despite a championship battle of twists and turns, was clear in the end, with Rosberg winning just five races in contrast to Hamilton's tally of 11.

With the British driver now a two-time title winner, and favourite to secure a third crown in 2015, Rosberg must return to the drawing board and come out fighting this year if he is to make the leap from multiple grand prix winner to world champion.

Despite his 2014 loss, the German's first experience of an intense championship fight will stand him in good stead for another shot in what should again be a two-horse race in the pace-setting car.

Here are five things that Rosberg must do to close the gap on Hamilton in 2015.

Rosberg is among the most PR-friendly drivers on the grid—perfect for shifting a few road cars and pleasing sponsors—but at times in 2014, his lack of title-battle experience shone through in front of a microphone.

It was most notable ahead of the Chinese Grand Prix, the race after his titanic scrap with Hamilton in Bahrain.

The German had been unhappy with one of his team-mate's defensive manoeuvres in Sakhir but told Sky Sports' Pete Gill that "we sat down and went through everything" before declaring that all was well again.

However, a confused Hamilton told the same source that a meeting hadn't taken place, giving the impression that a discussion wasn't even required.

It didn't take a rocket scientist to know which of the Mercedes drivers was telling the truth, but Hamilton's denial portrayed the British driver in a calm, relaxed light while making Rosberg appear needy and insecure.

In a high-pressure, head-to-head title race, every minor victory counts, and Rosberg, the intelligent operator that he is, should put himself in a better position to utilise the media in 2015.

As noted by F1 journalist Peter Windsor, Rosberg struggled comparatively to Hamilton in low-grip conditions in 2014, particularly on the harder tyres. 

Quite often in the second half of the year, he would struggle to manage his rubber, which would see him struggle with balance and therefore have no answer to Hamilton's pace. 

Take the wet Japanese Grand Prix—where, as per F1 Fanatic's team radio transcript, Rosberg repeatedly told Mercedes of his struggles with oversteer in the second stint and ultimately lost the lead—as an example.

The trouble for Rosberg is that the answer to excelling in such conditions is very much down to natural instinct and not the analytic and methodological skills for which the German is renowned.

Yet it is imperative that Rosberg works on his driving inputs in these circumstances if he is to match Hamilton in 2015.

Dedicating entire pre-season test runs, and even some grand prix practice sessions, to getting a grip should help his cause going forward.

One of Rosberg's biggest weapons was taken away from him in the latter stages of 2014, when a partial ban on team radio was introduced on the eve of the Singapore Grand Prix.

It was little coincidence that the German only added only one more victory to his season's tally from that point, and things will only get more difficult in 2015, with the ban set to be broadened.

Rosberg relied heavily on pit-to-car radio in 2014, frequently absorbing information provided by his race engineer, Tony Ross, during grands prix. This was particularly evident in Canada, where Rosberg managed an MGU-K failure to finish on the podium while Hamilton, with the same problem, was forced into retirement.

Should an identical situation occur in 2015, there is a greater chance that both Mercedes drivers, with limited external help, would be destined for an early bath, placing an emphasis on drivers to perform independently.

Rosberg's dependence on team radio was cruelly interpreted by some as the work of a driver who needs to be spoon-fed, but it would not be unfair to suggest he should become comfortable with going it alone in 2015.

Wheel-to-wheel combat was undoubtedly Rosberg's biggest weakness in 2014, and he, to his credit, acknowledged this, telling Sky Sports' Pete Gill and James Galloway: "I need to work on the racing a little bit."

Throughout the campaign, Rosberg lacked the assurance and imagination of Hamilton in racing conditions. 

His failure to employ the undercut technique during the pair's race-long fight in Bahrain saw him miss out on a victory that was there for the taking, while Hamilton overtook the German with ease in Italy, Japan and the United States.

In contrast, whenever Rosberg tried to overtake Hamilton, he couldn't make a move stick, with the German eased off the track in Hungary, hitting his team-mate in Belgium and locking up in Russia. 

And it wasn't just against Hamilton that he was found wanting either.

A potential victory at Spa was lost when Rosberg dithered as he made his way through traffic, and he was stuck behind Jean-Eric Vergne's Toro Rosso for an unacceptable length of time in Hungary, which saw him denied another win.

A more aggressive, confident stance in racing is key if he is to become world champion in 2015.

Rosberg was not punished for his controversial off in qualifying at Monaco in 2014, which ruined his team-mate's final shot at pole position.

However, subsequent events—his collision with Hamilton in Belgium—suggest that there was at least a hint of malice in his trip down the Mirabeau run-off area.

And who can blame him if there was?

With Hamilton still among the most emotional and easily distracted drivers in F1, it makes complete sense for Rosberg to continue to use every trick in the book—even the dark arts—with the goal of unsettling his rival.

Post-Monaco, Hamilton made errors of varying degrees in each of the following seven grand prix weekends—from a couple of mistakes in Q3 in Canada to a lacklustre start in Italy—proving that the two-time world champion can be vulnerable when knocked out of his rhythm.

It is imperative that Rosberg does that knocking, keeps prodding away and exposes the one enduring weakness of Hamilton's game.

It might not win him many friends, but it might just win him a world championship.