Luke Hole, 29, who played for Pontyclun RFC in Rhondda Cynon Taff, had been taking part in the Majorca Beach Rugby sevens tournament.
Friends were unable to rouse him on Monday morning after the two-day event. Emergency services were called but pronounced him dead.
One friend said Mr Hole was "the life and soul of the club".
He described the player as "totally committed to all of his friends", and said the death had left everyone "heartbroken".
The friend added: "He would do anything for anyone and this is just devastating, especially for all the boys that were with him in Spain.
"My thoughts are with them and his girlfriend and all his family.
"It's just so sad for everyone that knows him."
The team, known as the Pontyclun Badgers, had travelled to the Spanish island for the long weekend, where competitors from across the UK and Europe were taking part in the tournament.
Pontyclun RFC posted a message on its Facebook page, saying: "Absolutely heartbreaking. Our thoughts are with his family, loved ones and friends."
A spokesman for the Foreign Office said: "We are supporting the family of a British man following his death in Mallorca, Spain."
A rugby player taking part in a beach rugby tournament with his team in Spain has been found dead in his hotel.