As the 2021 season resumes, Lewis Hamilton admits that he's probably facing his toughest challenge yet.

Despite claiming that "it was nice to have a few weeks off to rest a bit and spend some time on the jet skis", there can be no doubt that Max Verstappen was in fact chomping at the bit, wishing the time away in order that hostilities could be resumed.

Over the course of two weekends in Britain and Hungary, first lap incidents involving his Mercedes rivals saw his 32 point lead become an 8 point deficit. Indeed, with Red Bull scoring a pitiful 5 points over the two weekends its 44 point lead became a 12 point deficit.

Ignoring the circumstances of Verstappen's title lead fell apart, Lewis Hamilton admits that he expects the second half of the season to be his toughest yet.

"We knew how good they would be at the beginning," he told reporters at Spa today, "we've obviously seen the speed and the competitiveness of them in the past.

"Of course, as we've got through the season, they've got stronger and stronger and it's been harder for us as we've gone on, we've had a bit of a difficult patch but we got back to operating how we have done in the past," he added.

Indeed, for other than those first lap 'mishaps' at Silverstone and the Hungaroring, as Red Bull's grip on the titles tightened, Mercedes was forced to do an about turn on its previously stated policy and introduce a number of updates. Updates, which helped in swinging championship hopes back in its favour.

"It's going to be close," admitted Hamilton, "it's going to be tough this second half of the season. The first half was definitely one of the toughest and I expect it's going to be pretty much the same in the second half, if not more difficult."

Of course, Hamilton doesn't need reminding that the 2016 title fight was particularly hard, albeit from the guy in the adjacent garage. Asked how the fight with Verstappen compares with that with Nico Rosberg, Hamilton said: "It's exactly the same, if I'm really honest, whether you're fighting your team mate or another team, I would say in terms of how much you need to dig.

"But it's a different journey that you go on when it's internal," he continued, "the journey you go on with a smaller group of people within your own team, as opposed to a whole team fighting another team. It's a much better dynamic, a much more enjoyable journey."

Talking of teammates, when asked about the ongoing saga regarding his teammate for next season, Hamilton said that his relationship with Valtteri Bottas is "better than ever".

"I've obviously been vocal in the past for my loyalty to Valtteri and worked incredibly closely with him," he said. "I think our working relationship is better than ever.

"Toto's a great leader and as I said in the past we've always stayed connected," he added. "Of course, we talk about these things and naturally we're part of the same team, we want what is best for the team moving forwards. We want to win more championships so we just have conversations but at the end of the day it's down to him and the board at Mercedes to make that decision.

"I am part of the team so I support whichever way they go naturally. I am just trying to put all my energy into the best I can this season."

Check out our Thursday gallery from Spa, here.