Macarthur FC veterans Benat Etxebarria and Markel Susaeta have both retired following the Bulls' inaugural A-League season.
The Basque duo were both influential for the Bulls, who made a semi-final in their first season - Susaeta scoring five goals in 23 games and Etxebarria playing in 24.
Susaeta, 33, played 507 games for Athletic Bilbao that included La Liga, UEFA Champions League and UEFA Europa League appearances and was capped for Spain in 2012.
The winger played 10 games for Melbourne City in 2019-20 before joining Macarthur this season.
Etxebarria, 34, a midfielder who won four caps for Spain, retires after 459 professional matches, including long stints at Athletic Bilbao and Real Betis.
"We have been extremely fortunate to have had players of Benat and Markel's calibre join our football club and to have them part of our inaugural playing squad was very special," coach Ante Milicic said.
"Whether on the training park or during matches, the knowledge and experience they have shown and provided the younger players in our squad has been invaluable.
"We wish them and their families safe travels as they head back to Spain."
The duo's retirement follows that of former captain Mark Milligan, who is moving into the Bulls' coaching staff.
Macarthur are soon expected to seriously bolster their squad for next season.
They have been linked to Johnny Warren Medallist and former Wellington captain Ulises Davila, former Central Coast Mariners playmaker Daniel De Silva and Melbourne City winger Craig Noone.