López, who won the Tour de Suisse and Milano-Torino in 2016, has not raced since Il Lombardia last October. The 23-year-old Colombian fractured his tibia less than a month later, crashing into a roadside curb during a training ride in his home country.
Initial team prognostications pointed to a possible return to racing in April, with the expectation that López would ultimately race the Tour de France in July. Even as April passed by without López returning to competition, however, he was still slated to start the Tour of California. Plans to race in California have since been scrapped after further medical evaluations in Europe led to a determination that his return to racing should be postponed to allow for further recovery.
López has since returned home to Colombia. He is now aiming to return to competition in June, According to Astana.
In López's absence, Astana's roster for the Tour of California is headlined by Classics specialists and youngsters, with veterans Matti Breschel and Laurens de Vreese and up-and-comers Truls Korsaeth and Riccardo Minali among the selection.
Astana for the Amgen Tour of California: Matti Breschel, Laurens De Vreese, Daniil Fominykh, Arman Kamyshev, Truls Korsaeth, Riccardo Minali, Ruslan Tleubayev and Artyom Zakharov.