The USA international joined Wales’ Capital Region in the summer and made seven appearances, scoring a try on his PRO14 debut against Cheetahs.
However, while Manoa made the move to Cardiff, his wife and five children remained in California, making his transition all the more difficult.
Cardiff Blues head coach John Mulvihill informed the squad of the decision earlier this week and Manoa will now remain in the United States.
“Naturally we are very disappointed to lose a player of Samu’s quality but we understand his situation and it’s the right decision to release him from his contract on compassionate grounds,” Mulvihill said in a statement.
“It is always challenging to adapt to a new environment, particularly when your family are on the other side of the world.
“We appreciate all the effort Samu has put in during the short time here, he is a good man and gave his all. We wish him all the very best for the future.”
— Cardiff Blues (@cardiff_blues) January 4, 2019
“My sincere thanks goes to Cardiff Blues and John Mulvihill for the opportunity, everything they have done for me and their understanding in recent times,” Manoa said in a statement.
“To represent Cardiff Blues was a great honour and experience for me. I welcomed by my teammates and the great supporters from day one and I really appreciate that.
“The Blues have a great group of players and coaches and I wish them all the very best for the remainder of the season.”
The Blues currently sit fifth in their PRO14 conference with an even record of six wins and six losses.
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