 On 13 September 2013, he was signed on loan by French club Ajaccio to gain further first team experience.Ajaccio were then managed by Italian manager Fabrizio Ravanelli (who was also a former teammate of Conte's).Diagne was loaned out to Belgian club Lierse in January 2014, and made his debut on 31 January against Anderlecht, scoring in the 25th minute.