Ghana international Kevin-Prince Boateng arrived in Portugal on Tuesday where he is set to sign a two-year deal with Sporting Lisbon, local media reported.
The 28-year-old midfielder, who is also a German citizen and has played for Schalke 04 since 2013, did not make any comment as he was shown on television at Lisbon airport.
The Royal Blues kicked Boateng out of the squad last May after a shock defeat at Cologne.
Schalke finished sixth in the Bundesliga and missed out on a Champions League berth for the first time since the 2010/11 season.
Boateng was allowed to talk to other clubs to negotiate a transfer and had already been linked to former club AC Milan.
He played for Borussia Dortmund and Portsmouth in England before moving to Italy where he played 101 matches for AC Milan and 60 with Schalke after his return to the Bundesliga.
Boateng has 15 caps for Ghana who sidelined him before the 2014 World Cup. His younger brother Jerome, 27, a defender with Bayern Munich, has opted to play for Germany.