David Ferrer
Ferrer will join fellow Spaniards Tommy Robredo, whom he beat in 2007 to win the title, and former world No 1 Juan Carlos Ferrero at the tournament.
Ferrer, currently ranked 18 in the world, has made at least the quarterfinals in five previous appearances at Auckland.
His highest world ranking was No 4, reached early last year.
"David is very popular in Auckland and has been adopted by the crowds," tournament director Richard Palmer said.
"He has been inside the world's top five players, which is no mean feat, and his record at the Heineken Open speaks for itself."
Also confirmed is former world No 3 David Nalbandian of Argentina.
The tournament will be played from January 11-16.
