The driver Mercedes should sign for 2019

When Mercedes turns its attention to nailing down its drivers for the 2019 Formula 1 season, it will not be short of options. Keeping hold of Lewis Hamilton, champion in three of the past four years, will be its priority, but the occupant of the second seat is less certain.

Valtteri Bottas is in a strong position as the incumbent but he will need to take a big step forward this year, while Mercedes junior Esteban Ocon would be a fine choice for promotion.

Outside the Mercedes family there is a plethora of drivers on offer, but taking all possible options into account, the driver at the top of the list should be Daniel Ricciardo.

Ricciardo ticks all the boxes. He is phenomenally quick. He can deliver over one lap and over a race distance. He knows how to win, having stepped onto the top step of a rostrum five times.

Mercedes needs a winner who can be relied upon to get the most out of the car consistently. Ricciardo has proved he can do that.

Nico Rosberg struggled with the pressure of being Hamilton's team-mate. He said it took every effort he could muster to beat his childhood friend and win his first world title in 2016. Such was the intensity of the challenge that he retired straight afterwards, not wishing to put himself (or his family) through that again.

Ricciardo is one of the few drivers on the grid who can cope with that sort of pressure. In 2014, promoted to Red Bull alongside the defending four-time world champion Sebastian Vettel, Ricciardo was expected to fall well within the four-time champion's shadow. Instead, he excelled in a sub-par car - winning three races to Vettel's zero - and finished third in the drivers' championship, 71 points and two places clear of his more decorated team-mate.

In 2016 he outperformed highly-rated Max Verstappen, finishing third in the championship again and describing the year as his best ever in F1. Last year was tougher, as he struggled to get on top of the new-generation cars and tyres. But he still finished ahead of Verstappen in the championship, which demonstrates his ability to deliver points even when things aren't always going his way.

A driver of that calibre could rock the boat. Mercedes and Hamilton have recent experience of how that can pan out. But Ricciardo is different.

The Australian is someone who you just get on with. It's not in his nature to be disruptive, but equally he's not afraid to say what he feels - such as after the Monaco Grand Prix in 2016 when a botched pitstop cost him victory for a second successive race. He sat down with the team after that to clear the air and both moved on quickly, rather than let it fester and provoke internal discombobulation.

Mercedes will need to think hard about how its driver policy will evolve beyond 2018. Hamilton and Rosberg did not get on as team-mates. The partnership did not work. It threatened to become poisonous.

So when Rosberg departed of his own accord, Mercedes was given the chance to change the dynamic. The choice was limited, given the timing, and they went for a safe option. In Bottas they got a quick driver who fitted in well to the Mercedes family. His unprickly nature helped sponsor a harmonious atmosphere; Hamilton said that was a key factor in the outfit securing its fourth double world championship. Team boss Toto Wolff agrees.

"Nico put us in front of a fait accompli - there was not even a discussion [about retiring] - and it was difficult to find the right driver, but we gave it some time to decide and eventually we got just the right guy into the team," he says.

"In the past I always believed that a very fierce rivalry between team-mates would be good for the team because they would be pushing each other. The lesson I learned is that is probably not true - you need two team-mates that perform at a high level that keep pushing each other in the car, but the rivalry shouldn't spill over into controversy outside of the car.

"The mindset and the relationship between the two [Bottas and Hamilton] made us stronger, gave an open and honest environment, and fundamentally our very fast, difficult car we got it into a good place also because the two worked so well together."

"He's a great character, he always brings a lot of positivity within his team. I think it's interesting, I think it's cool, I take the compliment that people say they want to race against me" Hamilton on Ricciardo

But Bottas has yet to prove he is part of that elite group capable of winning the title. Had Hamilton not been at the team last year, Sebastian Vettel would have won the title and Ferrari would likely have won the constructors' championship.

Ricciardo is definitely one of that elite group of championship candidates. He has that hunger to succeed and the feeling within the paddock is that he is capable of winning the title. Mercedes will be wary of pairing him with Hamilton, after what happened with Rosberg - but the dynamic will be different. Publicly, both have suggested they would have no problem teaming up. Ricciardo said he would like to race against Hamilton in the same equipment while the Mercedes driver is in his prime.

When asked by Autosport about those comments, Hamilton said it would be a "privilege" to have Ricciardo in the garage next door - but that Ricciardo should be aiming to conquer his current team-mate before setting his sights on someone else.

"He's a great character, he always brings a lot of positivity within his team," he added."I think it's interesting, I think it's cool, I take the compliment that people say they [want to race against me].

"I don't necessarily believe that people want to be up alongside me, because that is not always the best thing for an individual. But in some cases, it could be a really good thing because it can help you grow.

"You look at Daniel, he's got a great driver in his team-mate, and to be honest, he has got to really work to outperform him first. You've always got to beat the person you're with before you can look at competing against someone else and beating them - that's just my personal opinion."

Hamilton makes a fair point. Ricciardo may well have beaten Verstappen in the points standings, but in other areas of comparison, it was the Dutchman who came out on top.

When both cars finished in 2017, Verstappen beat Ricciardo five times to two. In qualifying, Verstappen excelled and led the way 13-7 in the head-to-head. And in terms of race wins, Verstappen secured two to Ricciardo's one. Verstappen even won the fastest lap tally nine - seven.

Ricciardo says that sometimes he would push too hard to find a solution to a particular problem, before realising later in the season that he needed to "just throw the book out the window and drive it".

The Australian is convinced he has made a breakthrough and is working hard over the winter to ensure he can get out of the blocks quickly this season. If he does that, he should be in pole position for the Mercedes seat.

Ricciardo may not have a contract for next year, but he is a man in demand. Red Bull is desperate to keep him. Renault retains an interest, having previously made a bid. And Ferrari president Sergio Marchionne might have said that promoting a young driver would be his next step if Kimi Raikkonen doesn't deliver this year, but it's one thing to say you'll go against a long-held policy and quite another to follow through.

Ricciardo is in a great position. He says he will wait to see how Red Bull performs this year and take his time to make a decision on his future. He can focus on delivering on track and let everyone else fight over him.

Team boss Christian Horner says if Ricciardo leaves for Ferrari or Mercedes, he would be a "number two" driver. That may well be the case at Ferrari, but less likely at Mercedes - and it could arguably become the situation at Red Bull if he stays, given that Horner has urged Verstappen to build the team around him.

Yes, Ricciardo will have a tough time proving he is capable of beating Hamilton. After all, Hamilton has been in situ for five years. He has gelled in the way Michael Schumacher did at Ferrari. But nothing lasts forever and Mercedes will have an eye on the future.

Hamilton has yet to sign a new deal beyond this season but it's almost certain he will. He has said he expects to continue to race until 2020 - thereafter, who knows?

With Verstappen and Vettel off the table until at least 2020, signing Ricciardo would be a tremendous bit of business for Mercedes. Even if he can't beat Hamilton in 2019 or '20, he will likely push him harder than Bottas, which is particularly important for the constructors' championship if Ferrari and Red Bull's threat intensifies. Should Hamilton leave before the end of his contract or not extend his stay, Ricciardo would be a driver you could have confidence in to lead the team and challenge for the world championship.

When Ricciardo signed his last Red Bull contract, it was with an eye on a long-term future with the team and the idea that he could build the team around him. But then Verstappen rocketed into the picture.

Ricciardo has complete confidence that he can beat Verstappen and has no fears that Red Bull will start favouring his team-mate, but there will be something in the back of his mind whispering that this might not always be the case.

At 28, he also knows the next contract will cover his peak years in F1, so breaking free of the family that gave him his shot in F1, in the way Hamilton did by leaving McLaren for Mercedes, would be difficult but it could also be shrewd.

His personality, work ethic and speed means he would settle in quickly to any team that he joins - very few drivers can say that. Mercedes would be no different and you would expect him to get up to speed quickly.

He was unfortunate that he joined Red Bull at a time when it suffered a dip in form, having won the previous four world championships. By joining Mercedes when the regulations remain relatively stable, he's less likely to go through that again.

This move could well define whether he will ever become a world champion and whether Mercedes can continue to dominate after Hamilton retires. It's why Mercedes signing Ricciardo for 2019 would be a win for team, driver and Formula 1.