The 40-year-old American had a stellar start to his 2012 season with a second place result at Italy's Tirreno-Adriatico, Horner's return to racing after an eight month hiatus following his crash in the 2011 Tour de France.
Horner skipped the Volta a Catalunya to heal a minor injury sustained at Tirreno-Adriatico, but in his next race he finished ninth overall at the Vuelta al Pais Vasco. Horner rode the Ardennes Classics and then returned to the United States for his Amgen Tour of California title defense.
Horner will have strong support on what's considered the most difficult route in the California race's history from teammates such as Tiago Machado, fresh off a 15th place overall result at the Tour de Romandie, plus reigning US professional champion Matthew Busche, the 2011 Amgen Tour of California revelation who was instrumental in shredding the peloton on last year's summit finish at Mt. Baldy where then teammates Levi Leipheimer and Chris Horner finished together in first and second place.
Strong men Gregory Rast, Markel Irizar and Jens Voigt will provide plenty of horsepower on flat to rolling terrain while New Zealand's George Bennett and 2010 US pro road champion Ben King round out the team's line-up.
The Amgen Tour of California begins May 13 in Santa Rosa and concludes on May 20 in Los Angeles.
RadioShack-Nissan roster for Amgen Tour of California:
George Bennett (NZl), Matthew Busche (USA), Chris Horner (USA), Markel Irizar (Spa), Ben King (USA), Tiago Machado (Por), Gregory Rast (Swi), Jens Voigt (Ger)