In 2012 the Great Britain men’s road race team enjoyed the perfect buildup to the event that opened the home Olympic Games; it was only on the day itself that the plan stalled. This year a bitter selection controversy has marred the run-in but the upshot is a quintet led by the triple Tour de France winner Chris Froome have far greater strength in depth than four years ago.

On a London course where a field sprint was the most probable outcome, GB had no option but to back Mark Cavendish but on the day his four team‑mates were unable to control the race as they had hoped, try as they might, and there was no plan B.

On Saturday the polar opposite applies: the course is far tougher, the race will be one of attrition until a core of strongmen remains and GB will field four potential medallists: Froome and Adam Yates in the obvious list of favourites, Geraint Thomas and Steve Cummings among the outsiders, plus the hard-working Ian Stannard.

Although it now seems like a mere footnote given the furore over Lizzie Armitstead, the damaging tension over Cummings’s selection was hardly the ideal preparation and further reflected the wobbliness within British Cycling following the departure of their head coach, Shane Sutton, in late April.

Peter Kennaugh was initially named in the lineup in spite of the fact he had not raced since May, prompting Cummings to call for the resignation of the coach Rod Ellingworth. Eventually, Kennaugh withdrew from the team, meaning Cummings could be drafted in alongside the one-day Classic winners Yates and Thomas, and the Tour winner Froome.

There has been no course this tough for an Olympic road race in recent memory. The limitations of the host cities tend to mean truly demanding climbs are impossible to include. The profile of the Rio course is different. The eight short steep climbs of Grumari and Greta Funda will do some damage early in the 237.5km but the decisive moves will be made on the eight-kilometre ascent of Vista Chinesa, tackled three times in the final 80km.

The Rio course looks comparable with one-day Classics such as Liège-Bastogne-Liège, but not quite as tough as a major mountain stage of the Tour de France, while the 12km flat run-in to the finish in Fort Copacabana will favour anyone with either sprinting ability or tactical nous who can get over the climbs.

The list of potential medallists is lengthy, pointing to a tense race with most waiting to show their hand until the final laps. The Spaniard Alejandro Valverde is an old hand at losing world road titles – six medals to his name but no gold – but the course is perfectly suited to his blend of climbing and sprinting, although his past doping ban would not make him a popular gold medallist.

Ireland’s Daniel Martin showed strong climbing form during the Tour de France and is perhaps the best one-day racer in the world in terms of tactical astuteness, making up for the fact he has a relatively poor sprint, while Rui Costa of Portugal, Vincenzo Nibali and the 2014 world champion Michal Kwiatkowski offer a similar blend of climbing skill, tactical awareness and a certain amount of speed at the finish, as do the French duo of Julian Alaphilippe and Romain Bardet.

In the first South American Games, Colombia field a strong squad around the London silver medallist Rigoberto Uran, who may have to play second fiddle to the Tour de France strongmen Sergio Henao and Jarlinson Pantano or the Giro d’Italia revelation Esteban Chaves.

Teams in the Games are small – major nations field four or five riders – so it is impossible to envisage any nation trying to control the race. That in turn could play into the hands of a rider willing to chance their arm in an early move, which is where Cummings – the winner of two stages in the last two Tours de France from long-distance breaks – gives GB an obvious option.

As for Froome, he won his third Tour de France with unexpected attacks on the Col de Peyresourde and on the sprint stage to Montpellier, which pointed to a newfound tactical awareness to go with his obvious climbing ability. However, the 31-year-old has never won a one-day race.

He is usually reliant on strong support from Team Sky in the Tour to back up his pure climbing strength, so it is impossible to predict how he will function if, say, he finds himself alone with a group of a dozen in the final kilometres and an Olympic medal beckoning.

In that domain a lack of experience should be a weakness but it can also be a strength; when Froome races on instinct alone he can be at his most dangerous.

• You can follow the men’s road race live on the Guardian website on Saturday 1.30pm BST