Claudio Nunes (born 23 March 1968) is an Italian professional bridge player. He is a five-time world champion, a World Grand Master of the World Bridge Federation (WBF), and the WBF second-ranked player as of April 2011. He is one of 10 players globally who collected the Triple Crown of Bridge.
Nunes was born in Rome. His regular partner for many years is Fulvio Fantoni, the first-ranked World Grand Master (April 2011). Fantoni-Nunes are generally regarded as one of the top pairs worldwide. They play "Fantunes", for their surnames, an innovative bidding system characterised by natural but forcing one-level opening bids in all four suits.
Since 2011 Fantoni and Nunes are full-time members of a team led and paid by the Swiss real-estate tycoon Pierre Zimmermann, under contract expiring 2016. From 2012 all six members would be citizens of Monaco and the team would represent Monaco internationally. The team finished third in the 2010 world championship, not yet full-time, and competed in the 2011 European Bridge League open championship (neither is a national teams event).
Early on 14 September 2015, expert player Kit Woolsey reported at Bridge Winners (bridgewinners.com) some conclusions of an investigation of play by Fantoni–Nunes in the 2014 European championship for national teams, where the pair represented second-place Monaco. The investigation was conducted by a team led by Boye Brogeland of Norway, who had started in August a public campaign to clean up the top ranks of bridge. Fourteen hours later, that article was prefaced by a note from the website editors: "Bridge Winners has received overwhelming evidence alleging improper communications between the world's #1 and #2 ranked bridge players, Fulvio Fantoni and Claudio Nunes, during the 2014 European Championships." The evidence included analysis of video recordings of 10 matches played by Fantoni–Nunes during the tournament, wherein the vertical or horizontal orientation of a card played on the table correlated with possession of a high honor in 82 out of 85 cases.