Manchester City captain Ilkay Gundogan is set to leave the treble winners to join Spanish Barcelona on a free transfer, according to reports.

As his City contract expires at the end of June, Gundogan is expected to complete his move to the Spanish champions, who are widely reported to have offered him a three-year deal.

According to reports, City was prepared to offer their 32-year-old captain a new one-year contract with an additional 12-month extension.

However, the news of Gundogan’s impending transfer to the Camp Nou broke on the same day that City agreed to sign Chelsea midfielder Mateo Kovacic for £30 million ($38 million).

The loss of Gundogan, whose leadership and penchant for scoring crucial goals were instrumental to City’s success under Pep Guardiola, would be mitigated by Kovacic’s versatility and experience.

Guardiola’s Premier League champions City won the FA Cup after Gundogan scored twice in the victory over Manchester United, and they went on to win the Champions League after defeating Inter Milan.

The German national team player appeared in 51 games this season, scoring 11 goals, six of which came in his last seven games as the race for the treble heated up.

City are only the second English team to ever win the treble in a single campaign.

Gundogan will be remembered fondly by City fans as one of the club’s understated cornerstones during their illustrious era.

In his seven seasons with City, the former Borussia Dortmund midfielder won the Premier League five times, the FA Cup twice, the League Cup four times, and the Champions League once.

Gundogan is a close friend of City manager Pep Guardiola’s from their time spent together in the same posh Manchester apartment block.

City reportedly did not want to match Barcelona’s offer, likely due to Gundogan’s age, and appears to have made the practical decision to let him leave.

Photo by EPA/SEDAT SUNA