Middlesbrough are set to be busy in the transfer market this summer as they look to strengthen their side in the hopes of gaining promotion back to the Premier League.
Boro have not been in the Premier League since they were relegated in 2017, and they have been attempting to find a route back there since.
While part of the Premier League, they have had some fantastic players, and even in their bid to return, they have also welcomed incredible talent to the Riverside; however, this talent sometimes opts to leave, and this has seen the club make some massive profits.
Middlesbrough are now linked heavily to signing Callum Brittain from Blackburn Rovers, while other players have been linked with moves away, like Finn Azaz.

EFL Analysis brings you the five most expensive sales the club has ever made.
- READ MORE: Blackburn Rovers set Callum Brittain price tag, Middlesbrough are not ‘a million miles away’
5. Yakubu – £14.2 million
Yakubu was an expensive signing when he joined Middlesbrough in 2005 from Portsmouth.
It could have been a horrible risk for the club, and the Nigerian could have flopped, but everyone at Middlesbrough will remember Yakubu fondly, as he helped them reach the 2006 UEFA Cup final.
He spent two full seasons at the club, playing in 102 matches in that period, and he was prolific, scoring a total of 35 goals.

It was a sad day when he moved to Everton in 2007; however, his £14.2 million price tag probably helped.
4. Marten De Roon – £14.4 million
The Dutch international did not have as memorable a period as Yakubu, or one that he may have hoped for when he joined from Atalanta.
Marten De Roon joined Middlesbrough upon their return to the Championship under Aitor Karanka.
However, he would not be able to help the club remain in the division, as they were relegated to the Championship.
De Roon would then exit the club to return to Atalanta ahead of the following campaign, having played just 36 matches at Boro.
3. Ben Gibson – £14.6 million
Currently, Ben Gibson is playing his football at Stoke City after moving between Burnley and Norwich City after he left Middlesbrough.
The local lad grew up with Boro and decided to leave the Riverside as they struggled to return to the Premier League.

Gibson had impressed at Middlesbrough in both the top flight and the Championship.
He signed for Burnley when they were in the Championship under Sean Dyche in the summer of 2018 after 203 games for Middlesbrough, a move he may have regretted after he struggled to break into the Clarets side.
2. Adama Traore – £17.3 million
The winger was brought in from Aston Villa in the summer of 2016, after the Villans were relegated to the Championship as Middlesbrough earned promotion.
Adama Traore had shown flashes of brilliance in the Villa side that seriously struggled, and it was hoped he could flourish in the Middlesbrough side.
He spent two seasons at the Riverside, finding the first season tough as Traore suffered his second straight relegation.
However, he impressed in his second season while in the Championship to earn him a move to Wolves, where he would properly thrive.
1. Emmanuel Latte Lath – £18.4 million
The Ivory Coast international was another acquisition from Atalanta on this list, joining the club in the summer of 2023.
He would leave the club to move to the USA, where he would sign for Atlanta United for an MLS record fee of £18.4 million.
Emmanuel Latte Lath was prolific in his two seasons at Middlesbrough, as he scored 29 goals in just 67 matches.
However, the fee the club received for him could not be rejected, as they could have been able to spend the money to strengthen a number of key positions to push towards promotion.
