Sunderland have enjoyed a fair degree of success in the transfer market in recent seasons as Kristjaan Speakman has unearthed gems to bolster the squad.

The likes of Ross Stewart, Dennis Cirkin, Jack Clarke, Alex Pritchard, and Patrick Roberts have all joined the Black Cats since the start of 2021 and are now key players for the club in the Championship.

However, transfer windows do not always go right and Sunderland have had their fair share of disappointments over the years, both in terms of bringing in underwhelming acquisitions and failing to land top targets.

One player the club endured a nightmare with was current Manchester City superstar Kevin De Bruyne, as Steve Bruce once eyed him as a potential signing.

Back in the summer of 2011, it was reported that the Black Cats were one of the teams lining up a swoop to sign the Genk attacking midfielder, who was 19 at the time.

Aston Villa were also said to be vying for his signature but he ended up penning a deal to sign for fellow Premier League side Chelsea six months later, in January 2012.

The gem racked up 17 goals and 36 assists in 113 outings for Genk and his performances in his home country were enough to convince Sunderland to be interested in signing him. However, they failed to land him and have had to watch on as he has enjoyed a terrific career to date.

He moved to Werder Bremen after a short spell at Stamford Bridge and burst onto the scene in the Bundesliga with 20 goals and 37 assists in 73 matches for the German side.

His form led to Manchester City signing him for a £55m fee in the summer of 2015 and he has produced an incredible 89 goals and 134 assists in 326 matches from central midfield to date.

The Belgian was named the PFA Player of the Year in the Premier League for both the 2019/20 and 2020/21 campaigns respectively. He was also named the Premier League Player of the Season in 2021/22, which means that he has been voted the best player in the division in each of the last three years by at least one of the two committees.

Fox Sports reporter Keith Costigan once described the midfielder as a "Rolls-Royce" who "runs the show" and De Bruyne could have been orchestrating Sunderland's play in the top flight during Bruce's reign if they had managed to snap him up from Genk.

Instead, he has gone on to feature in a Champions League final, win the Premier League four times, the League Cup five times and the FA Cup on a solitary occasion.

Therefore, the English boss certanly endured a nightmare by failing to sign the mercurial talent as his incredible achievements since that summer have proven that he is one of the best players in the country.