ESPN's driver of the year countdown: No. 9 - Valtteri Bottas

Moment of the 2017 F1 season (1:10)

ESPN's F1 experts reveal their picks for the standout moment of the 2017 season. (1:10)

Our countdown of 2017's best drivers continues with a man who impressed on his step up to the big time but struggled to match the season-long form of his teammate under the spotlight.

9. Valtteri Bottas
Championship finish: 3rd(305 points)

Considering he won the first three races of his career in 2017, it would be understandable to think our placement of Valtteri Bottas so low down our list of the season's top drivers is harsh.

Judging any driver's season has to be done in several ways. First, the circumstances around their season are important, but a driver must also be judged by what they did with the car at their disposal and how they did against the other driver in the same piece of machinery. Bottas' 2017 is a mix of good and bad and, unfortunately for his ranking this year, stands in direct comparison to this year's world champion.

We'll start with the good. Bottas was a late replacement for a world champion, joining a team at the start of one of the biggest aerodynamic overhauls in recent memory, going alongside one of the great talents of the modern era, Lewis Hamilton -- the man who had worn Nico Rosberg down so much in four seasons that he opted to retire rather than defend his 2016 title. It was Bottas' big break but all the cards seemed to be stacked against him.

After a difficult start to the year, he claimed a brilliant pole position at the third race in Bahrain, only to be hampered by a "perfect storm" of problems on the grid around the tyre pressures of his car. A lightning getaway at the next race in Sochi saw him snatch the initiative from Ferrari after its front-row lock out and he brilliantly held off Sebastian Vettel in the closing stages for the first win of his career. Another victory followed in Austria, and Bottas looked to be a title contender mid-way through the season. His form was rewarded by a one-year contract extension after the summer break.

So where's the problem? Well, this is where his season gets complicated. Bottas' new deal seemed to coincide with a loss in the form which had made his start with Mercedes so impressive. That not only happened as Hamilton found the peak of his own form, but also as Mercedes improved the car which had acted like such a "diva" earlier in the season. Bottas dropped out of contention of the championship as Hamilton took a stranglehold of it. Ferrari's implosion at the Asian leg of the season and Bottas' lack of results after the break meant the title was Hamilton's to lose in the closing races.

This is where the context of Bottas' season and situation is important. The pressure of a top team is different compared to a midfield team -- everything is under the spotlight, and success and failure is the fine line between winning championships and not winning championships. For the first time in his career, he had a car capable of winning an F1 title and he fell well short.

Bottas' slump led to Toto Wolff saying the Finn was lacking "the tick of killer" -- the instinct which separates good and great drivers in F1. He deserves some credit for how he recovered his season at the last two rounds -- claiming pole in Brazil, followed by pole and victory in Abu Dhabi, both crucial for his confidence going into 2018. But the fact this turnaround only came after Hamilton had wrapped up the title and, by his own admission, taken his foot off the gas means this cannot be weighed too heavily against Bottas' form when it actually mattered in the second half of the season.

Clearly, Bottas is incredibly talented and has the raw pace he needs to compete at the top of F1, but in 2018 he has to prove he has what it takes to be a world champion over a 21-race season. With a host of names set to be on the market for Mercedes to choose from as its decides its 2019 line-up, it looks set to be a make or break season for the Finn.