However, as tends to be the case with a lot of clubs, not every deal that gets completed ends up being particularly successful.
One significant move the Black Cats made in recent memory that could be filed into the disappointing category is their 2016 swoop for Didier Ndong.
Signed for a fee of £13.6m during the 2016 summer transfer window from Lorient, the midfielder ended up making just 54 appearances in a Sunderland shirt before joining Watford on loan in the 2018 January window.
After his temporary spell with the Hornets, the Gabon international was released from Sunderland in September 2018, just over two years into the initial five-year deal he signed with them.
In January 2019, French club Guingamp signed him before eventually moving the midfielder on to his current club Dijon in the following summer.
Back in October 2016, not long after making his move to the Stadium of Light, Transfermarkt rated Ndong’s market value at £9m, whereas it now stands at just a measly £1.8m.
Speaking on his move and time with the Wearside club, the 27-year-old had this to say on the matter:
“My transfer to Sunderland was not really my will. Loic Fery [Lorient president], who is a president who also loved me, was forced to sell me because Lorient needed money at that time.
“My first season went well in England. In terms of the game, there was no problem. But there was a lack of language and the absence of my family, all that hurt me. I also did not understand the good behaviour to have in Europe. I had some delays, I lacked professionalism. There are many things that I did not master.
“At one point in the season, the club was not doing well – it went down two times in a row – and it started chattering around me. There was also poor communication. It cost me dear.”
Taking all of this into account, it’s safe to say that this was a move that just did not work out for anyone.
Given how much money the club shelled out to sign him, they will have surely been having nightmares over this deal.
Looking at how the former Black Cat has seen his market value drop so dramatically since leaving England, his career certainly took a wrong turn when he joined Sunderland.