Ireland's Dan Martin expects Sunday's Road World Championships road race in Florence to come down to the survival of the fittest.

After a stellar year capped by April's win in the Liege-Bastogne-Liege classic and a Tour de France stage triumph in July, Martin is bidding to claim another high with the rainbow jersey in his sights.

But for a crash in the Vuelta a Espana, which saw Martin abandon the race and spend a lengthy period off the bike nursing his wounds, the 27-year-old Birmingham-born Irishman would be even more bullish about his chances.

As it is, Martin knows home favourite Vincenzo Nibali, Tour de France winner Chris Froome of Britain, Spain trio Alberto Contador, Joaquim Rodriguez and Alejandro Valverde and Colombians Nairo Quintana and Rigoberto Uran are in stronger positions entering the 272-kilometre event in Tuscany.

"I'm not as optimistic as I could've been, if I had have done the ideal preparation, which would've been the Vuelta," Martin, nephew of 1987 world champion Stephen Roche, told Press Association Sport.

“We’ll see. Anything can happen on the day. This time of year it is a case of one day you’re good, one day you’re bad. It’s the nature of it being the end of the year.

“I think it’s going to be a gradual whittling down of the competition. It’s going to be a real endurance race and a wearing down process.

“If you’re still there at the end, it’s going to be... it’s 272km, it’s immense. It’s a huge distance, seven hours. It’s going to be a hard race, but that’s what suits me.”

Martin has shown time and again he has the capacity to suffer. He added: “It would be incredible to be world champion. I already won the unofficial World Championships with Liege.

“This year’s been incredible and whatever else happens is a bonus; I said that straight after Liege. It’s not a normal race. It’s the end of the year, some guys are tired, some aren’t. Nibali’s said from the start of the year he’s really aiming for it, on home turf.

“All the competitors, the Colombians, Rodriguez, Valverde, they’re coming out the Vuelta strong. They’ll be the hardest guys to beat, all the guys who did the Vuelta, and that’s why I wanted to do the Vuelta.”

Martin's Ireland team-mate and cousin Nicolas Roche did complete the Vuelta, finishing fifth overall behind Chris Horner of the United States.

Roche and Martin could make a big impact on the race.

“Nico’s going to be there a long way into the race and hopefully we’ll both be there in the finale and we can play off each other,” Martin added.

“He’s had a really hard year as well. You don’t know what he’s going to come out with on the day. I’m not saying I’m the ultimate leader straight away. The form Nico had at the Vuelta, he could be the man as well.”

Like Ireland, Britain favour a tough race, as otherwise the likes of defending champion Philippe Gilbert of Belgium, Peter Sagan of Slovakia and Switzerland's Fabian Cancellara will come into contention.

British Cycling performance director Sir Dave Brailsford told Press Association Sport: "Sometimes at the worlds when the course is very hard, you get the situation where the course nullifies the racing. They get so cautious that they don't race, which wouldn't work in our favour. We'd like a hard race."

A hard race would suit Froome.

Brailsford added: "He's in good shape. He's had a big block at altitude, come back down, did the Canada races. He's going to be in terrific shape.

“The one thing about Chris is he’s a never-say-die character, he’s mentally robust and I’m sure the course will be in his favour.

“Hopefully we’ll try to make sure there’s enough going on and it’s hard enough to draw out the guys, so it’s a kind of war of attrition, rather than guys going off the front.”

Key to that scenario unfolding is a strong display by the British team, who can be expected to set the tempo early on, with the likes of Ian Stannard and Steve Cummings riding on the front of the peloton.

Sir Bradley Wiggins, Froome's predecessor as Tour de France winner, can also have an impact on the race. "Brad can play a big role and he's up for playing a big role," Brailsford added. "Somebody's got to take responsibility and make it hard."