Although Alonso has endured two difficult seasons since joining McLaren, Brown insists the two-time champion is not disillusioned by the team's performance since reuniting with engine supplier Honda.

Alonso finished the 2016 season in 10th position with 54 points, having wound up 17th the previous year.

Despite the recent lack of results, Brown considers the Spaniard as the best driver on the planet.

"I don't see Fernando as disillusioned at all," Brown told the official Formula 1 website. "I don't know him well yet, but I've met him a few times, and phoned him too, and I can tell you that he's buzzing.

"Also, even though our car wasn't fully competitive last season, some of his drives were stunningly good. Look, I'll be frank: I reckon he's the best driver in the world, period."

Vandoorne "the real deal"

Alonso will be partnered by Stoffel Vandoorne this season, the Belgian replacing Jenson Button alongside the Spanish driver.

Brown acknowledges that Vandoorne will face a big challenge racing against Alonso, but the American is convinced he will pass it with "flying colours".

"Stoffel faces a serious test," Brown added. "But, guess what, I think he'll pass it with flying colours. Our personal trainers tell me he's probably the fittest driver we've ever had, and he's incredibly focused and determined.

"He's fiercely intelligent too - you never have to tell him anything twice.

"His grand prix debut in Bahrain last year was sensational - he out-qualified and out-raced Jenson [Button] despite having minimal time to prepare for the weekend. In fact he only arrived in Bahrain on the Friday morning, straight off a long two-flight journey from Japan via Dubai.

"I think Stoffel will surprise a few people. He's the real deal."

McLaren won't be in front in 2017

Brown admits that, despite the big regulation changes coming into play this year, his team still needs more time before it can fight at the front of the field.

"I think our 2017 chassis will be a decent one," he said. "I'm not going to make any precise predictions - I'm not that dumb - but all the indications are that, relative to the targets we thought were realistically attainable under the new regs, our guys have done a very good job."

"We all know that 2015 and 2016 were learning years, and we won't be at the front of the grid in 2017 either. But we're working incredibly hard, together, as one team, and the progress is clear to see."