Monster Yamaha stand-in rider Josh Hayes has admitted the prospect of riding Colin Edwards' YZR-M1 in MotoGP free practice scared him to death but the two-time AMA Superbike Champion said he is also hugely excited about racing in Sunday.

Hayes was upgraded from testing the bike on Monday to participating in a full weekend's competition when Edwards was injured in the Sepang crash that killed Marco Simoncelli. He has never seen the bike or track, never ridden something so light or powerful, never used these Bridegstones and still went tenth fastest in the wet…

"It's been a very large mix of emotions. The circumstances by which I find myself here are not ones I am happy about and I would have happily have passed up this opportunity to have Marco and Colin here, doing what they do and be perfectly happy to test the machine. When the race was offered, there is this piece inside of you that gets really, really crazy and I am truly excited about it. At the same time I am scared to death," said Hayes, speaking to bikesportnews.com this evening.

"Everything about this has been such an unknown. There is a face inside of me that says I really don't care to race this machine. But anytime you put a chequered flag at the end of something, for a racer, there is a pressure. It doesn't have to be from anyone else, it's there. Everyone has asked me about goals and how can I give an honest answer when I know so little about it. That is the thing that is so scary about it.

"I know nothing about the machines. I know they are light in weight and they have a lot of power. I didn't realise how physically small they are. I saw Chaz Davies, who is a good friend, earlier and he goes, 'What do you think?' I said, 'It's a small machine.' He laughs, says 'You look like a giant!' turned around and walked off. 'Son of a bitch,' I thought!

"After our season was over eight weeks ago, it was the first time I said I was going to take a break. I have done nothing training-wise for two months - I rode my bicycle three times before I showed up here. Everyone else here is at the top of their game, they've raced three times in the last five weeks and are riding these bikes as well as they have every ridden them.

"Any of them showed up on a Superbike in New Jersey, they're going to have a hard time beating me. For me to show up here is really, really tough. I've never seen the circuit, I'm so bad at video games the couple of laps I did were useless, I had to put it on 'you-can't-do-anything-wrong setting, and it was a gross misrepresentation.

"All I have heard about the carbon brakes and Bridgestone tyres is how difficult they are to adapt to, so I have been working myself up to it and then you show up and it rains or it's drying - about the worst conditions you can have for learning a GP bike.

"I was pleasantly surprised with tenth in the wet but I'm not going to come here and tell these guys what they need to do to change their motorcycle. I pitted one time in two sessions, this last session I rode from start to finish, 24 laps and it is must a matter of getting laps on the bike. I'm just trying to understand what makes a GP bike go around a race track."

More from the erudite Josh Hayes tomorrow