Casey fought Paul Hyland at the University Arena in Limerick on 6 November 2010 for the European Super Bantamweight title which was previously held by Bernard Dunne. The original fight was supposed to be against Kiko Martinez who had held the title. However Martinez vacated the title citing a "rib injury" as the problem. Casey won the fight and is now European Super Bantamweight champion. On February 2, 2011 Casey was named Boxer of the Year at the Irish National Boxing Awards. Casey was then offered a fight with WBA World Super Bantamweight Title Guillermo Rigondeaux by Rigondeaux's manager Gary Hyde. Casey accepted this fight, thus relinquishing his European Super Bantamweight Title. The fight on 19 March 2011 was stopped with 22 seconds left in the 1st round, with Rigondeaux retaining his title. Willie Casey had a comeback fight on September 17, 2011 against veteran Frenchman Daniel Kodjo Sassau at the Kings Hall, Belfast, Northern Ireland. In the 7th round Casey dropped Sassou with a straight left cross and went on to win the fight with an 8th round TKO.