Italian cyclist Ivan Basso received a surprise visit from International Cycling Union (UCI) anti-doping inspectors on the eve of Saturday's season-opening classic Milan-Sanremo road race.
Basso's main rival in May's Giro d'Italia, Tour de France legend Lance Armstrong, received a surprise French doping test, the 24th in his career, earlier this week.
Basso, 31, who completed a 16-month doping ban in the Spanish drug case Operacion Puerto in October, continued his comeback with a fifth-place finish in the Tirreno-Adriatic last week.
Both riders are in Saturday's Milan-Sanremo but not among the favourites.
Seven-time-straight Tour winner Armstrong, 37, emerged from retirement earlier this year to bid for his first Giro and Tour double.
This year's centenary Giro starts in Venice on May 9 and ends in Rome on May 31.
