London - Tour de France favourites Vincenzo Nibali, Chris Froome and Alberto Contador admit the hectic nature of racing in Britain has been jangling their nerves.
All three have spoken about the dangers of riding on roads where some fans get over-excited and step out too far into the cyclists' path.
A Giant-Shimano rider clipped a fan on Sunday, knocking him over, while Team Sky's David Lopez hit another spectator on Monday.
That incident caused a crash further back in the peloton which saw former Tour winner Andy Schleck come down.
The sheer weight of numbers by the side of the road has been praised by riders but Nibali said that, alongside some surprisingly competitive racing for such early stages, it has been fraying nerves.
"It was very nervous at the finish because of the rain, there was a little bit of fear and there was a small crash but nothing too bad," said the race leader, who spent his first day in the Tour's famous yellow jersey.
"My first day in yellow was exceptional. We went off calmly, there was a bit of nerves and stress at the end, what with the rain, but my team helped me and I managed the emotion really well."
Such was the tension on the wet roads of London as the rain came down at the end of Monday's stage, which finished in front of Buckingham Palace with another victory for Marcel Kittel, that Contador spent much of the last few kilometres riding at the front.
"If he was in the front it's because he didn't want to take any risks," said Nibali.- High tension -
"There were many bends at the end, it was very difficult and he didn't want to take a risk, so he stayed up front.
"I was behind with (teammate) Jakob Fuglsang controlling, like me Froome was also behind with his teammate (Bernhard) Eisel. We left the sprinters to it."
Froome said he expected the high tension to continue.
"The big thing was to get through the stage, don't lose time or have any issues or incidents," he told ITV4.
"I'm feeling good. Tomorrow (Tuesday) we can expect a similar day but on day five we hit the cobbles and that will be quite a shake up, literally."
Former French cyclist Gilbert Duclos-Lassalle said the stress of this first week could catch up with some of the favourites later on.
"In this Tour it's fantastic, we started off in Yorkshire and for the favourites there's been a lot of pressure because we started with a first stage when it came to a sprint but there was a huge number of people (by the road)," he said.
"A second stage that felt like (Spring Classics) Liege-Bastogne-Liege or Amstel Gold Race with climbing and descents, and there were only the favourites present (at the end)."
He added: "Then (after Monday) we'll be into the north of France where they'll have to be wary of splits (due to wind) and then there's the famous cobblestone stage (five) so that will be practically a week under pressure for everyone.
"Normally in the past the favourites sat in the middle of the peloton, avoided splits and it was the sprinters who managed things (the first week) but here they've had to manage the race.
"You'll see that straightaway in the Alps, this pressure they've been under, because after this fast week we're into the Vosges and then the Alps and it will be up to them to play their cards right.
"Whoever hasn't been able to recover from this first week will pay."