Sunderland’s current stint in League One stems back to their last relegation from the Premier League at the end of the 2016/17 campaign.
It would be ridiculous to pin their relegation down to just one factor, but there was one noticeable departee who has since gone on to have an impressive career – Sebastian Coates.
The former Liverpool central defender, aged 26 at the time, was sold to Portuguese giants Sporting for a reported fee of £4.25m. He had played 16 Premier League games the previous year as Sam Allardyce led the club to survival ahead of their local rivals Newcastle, whilst also bidding farewell to Norwich and Aston Villa.
All three of those clubs are now playing Premier League football in the present day and Coates has established himself as a defensive powerhouse at the back for Sporting.
At the time of writing, Coates has won one league title, one Portuguese Cup and two Portuguese League Cups with the club he left Sunderland for, racking up over 200 appearances and playing in the Europa League and Champions League.
Per Transfermarkt, his current market value stands at £12.6m. This is a 196% increase from the £4.25m Sunderland sold the Wearside flop for in 2016.
Therefore, Coates may have been a player that the Black Cats let get away too soon. He has shown, since leaving the club, that he can be a solid defender at a very good level, with his soaring value in recent years highlighting this.
Sunderland’s 2016/17 season may not have been saved by keeping the central defender around, but his form for Sporting in recent years suggests that they could have fared better if they managed him correctly and got the best out of him.