National time trial champion Gianni Moscon has been selected for the race against the clock having helped Chris Froome to overall Vuelta a Espana victory in early-September.
Italy has won 55 medals at the World Championships but is still searching for its first podium appearance since Alessandro Ballan, and Damiano Cunego finished first and second at Varese in 2008.
While Cassani lost Vincenzo Nibali to injury for the Worlds, in the lead into the September 24 race Trentin won four stages at the Vuelta, Ulissi won the GP Montreal, Colbrelli was third at Bretagne Classic - Ouest-France, and won Coppa Bernocchi, while Viviani was second at the European Championships and has enjoyed success at Cyclassics Hamburg and Bretagne Classic-Ouest-France.
Daniele Bennati will be the road captain for the race with Alberto Bettiol, Alessandro De Marchi, and Salvatore Puccio also selected.
"We started the season slowly but now were winning a lot and winning well, it's the best moment of the season for Italian riders. That's good to know and encouraging. Riders like Viviani and Trentin are at their very best," Cassani told La Gazzetta dello Sport late last week.
"My riders are strong and intelligent. They know that their unity is their strength, and that together they can achieve a result that isn't possible alone. I don't see any friction between them."
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Former world champions Giorgia Bronzini and Tatiana Guderzo have been named in the women's squad with former medallists Elisa Longo Borghini and Rossella Ratto also earning their place in the squad.
"I think my season has been one of the best of my career," Longo Borghini told Cyclingnews. "It would mean the world, it would be the cherry on the cake for the season, but I don’t know. I will fight for it so hard, and I will try my best."
Elisa Balsamo, Sofia Bertizzolo, and Elena Cecchini have also been named in the team. Longo Borghini and Lisa Morzenti will both contest the time trial.
Italy for the 2017 Worlds;
Men's team: Daniele Bennati, Alberto Bettiol, Sonny Colbrelli, Alessandro De Marchi, Gianni Moscon, Salvatore Puccio, Matteo Trentin, Diego Ulissi, and Elia Viviani.
Women's team: Elisa Balsamo, Sofia Bertizzolo, Giorgia Bronzini, Elena Cecchini, Tatiana Guderzo, Elisa Longo Borghini (TT) and Rossella Ratto. Lisa Morzenti for the TT.
U23 men's team: Edoardo Affini, Vincenzo Albanese, Giovanni Carboni, Imerio Cima, Nicola Conci, Giovanni Lonardi and Matteo Moschetti. Time trial: Edoardo Affini, Paolo Baccio.
