Sunderland have had their fair share of transfer flops and gaffes over the recent years, as they have struggled to land the right player in the market at times.

They have also allowed players to leave too early and may look back on some of their decisions with regret as they have watched them go on to greater things.

One player with whom the club had a howler was Jon McLaughlin. They allowed the goalkeeper to leave the Black Cats on a free transfer in the summer of 2020 after failing to agree fresh terms with him.

He played 90 games in all competitions across two seasons with Sunderland from 2018 through to 2020, keeping 27 clean sheets in that time. This included 11 clean sheets in 32 League One outings in the 2019/20 campaign, keeping a shutout roughly once every three matches.

Then-Sunderland manager Phil Parkinson revealed that he did not want the veteran shot-stopper to depart the Stadium of Light, saying: “Jon is someone we would like to keep. The chairman and [Head of Football Operations] Richard Hill will be working on that.

“Jon’s recent record puts him up there as one of the best in this division. He is calm and has a lot of experience. At Bradford, he played in a lot of big promotion games. He played in big cup games too, and always handled the pressure well.”

Stewart Donald had valued the goalkeeper at £5m a year previously but was unable to convince the Scotland international to remain at the Stadium of Light as they did not offer him an acceptable contract.

This led to him signing a contract with Scottish giants Glasgow Rangers ahead of the 2020/21 campaign, and he has enjoyed a superb time with the Light Blues over the last two years or so.

He keep an eye-catching eight clean sheets in nine Premiership matches in his first season as his side won the league title under Steven Gerrard, whilst also playing once in the Europa League that term.

McLaughlin started the current campaign as Rangers' number one ahead of Allan McGregor and played in all Champions League qualifying matches as the club made it through to the group stages. He then made his full debut in the competition against Ajax in September.

The 35-year-old, who Joshua Barrie once dubbed "really sharp", is now a Champions League player, whilst Sunderland are playing in the Championship, and his achievements in Scotland suggest that Parkinson was right to want him to stay at the Stadium of Light.

However, Donald was unable to agree a new deal with the player, and that failure ended up being a howler as the shot-stopper has made his mark on the continent since leaving Wearside.