Robbin Ruiter has praised Luke O'Nien's discipline and development as Sunderland's remarkable rise from League One continues.

Former Sunderland goalkeeper Robbin Ruiter has praised Luke O'Nien's remarkable rise from League One to the Premier League and Europa League, insisting the defender's extraordinary discipline has been central to his success.

Ruiter spent two seasons at the Stadium of Light between 2017 and 2019 and was a teammate of O'Nien during the latter's first campaign on Wearside. The Dutchman has continued to follow Sunderland's progress since departing for PSV Eindhoven and admits he can scarcely believe the club's transformation.

O'Nien, who joined Sunderland from Wycombe Wanderers in the summer of 2018, has been one of the few constants throughout that journey. The defender played a prominent role during Sunderland's four seasons in League One before helping the club return to the Championship in 2022.

He subsequently established himself as a key figure under Régis Le Bris as Sunderland secured promotion to the Premier League in May 2025 and qualified for European football the following season. Ruiter believes O'Nien's progression is particularly impressive given the challenges Sunderland experienced during his own time at the club.

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"Not a chance,” Ruiter responded when asked whether he could ever see Sunderland making the Europa League. “Luke O'Nien is still here. His progress from League One to now being a Premier League player is incredible. It's all because of his discipline. Some people laughed at him for this in League One, but look where it has got him."

O'Nien's commitment and approach to professional football have become hallmarks of his Sunderland career, with the defender also assuming significant leadership responsibilities in recent seasons. The 31-year-old has experienced some of the club's lowest moments in modern history but has also played a part in its remarkable recovery.

Ruiter, meanwhile, says he remains a keen observer of Sunderland's fortunes and has been impressed by the recruitment and investment that helped transform the club. "The Premier League is such a difficult league, but there have been some great signings and the owner has done really well. Look at the possibilities now. Even in League One, I knew how big the club was. I follow Sunderland week in, week out, so I always know what's going on."

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