Celtic have picked up some significant transfer fees for some of their key players over recent years such as Odsonne Edouard, Kieran Tierney and Moussa Dembele among others.

One other player that the Parkhead club cashed in on that has proved to have been a great call from the Hoops is Adam Matthews.

Signed from Cardiff City back in the 2011 summer transfer window for a fee of £200k, the defender ended up making 150 appearances for the Bhoys across all competitions.

In those appearances, the £17k-per-week right-back scored five goals and delivered 22 assists before joining Sunderland in the 2015 summer window.

Sold for a reported fee of £2m, the Hoops made a significant profit on the player after four years of service at Celtic Park.

With 67 appearances for the Black Cats and two loan spells with Bristol City to his name, the Welshman was released from the Wearside club in the 2019 summer transfer window.

Not long after that, the former Hoops figure joined Charlton Athletic as a free agent, where he has since played in 87 games.

According to Transfermarkt, the full-back is currently valued at £540k, which is not only significantly lower than the transfer fee that Celtic picked up for him but also lower than the value of £2.7m that he was rated at during his days with the Hoops.

Having claimed to have "had issues" with his hamstrings by Lee Johnson, Matthews was plagued by numerous injury problems at Celtic.

This season has seen Matthews play in 26 League One games for the Addicks but only earn himself a rather uninspiring overall performance rating of 6.53/10 from WhoScored.

To further highlight how disappointing he's been in this campaign, the Wales international has only been able to average 0.7 tackles and interceptions per game, which is rather unimpressive for a defender.

Taking all of this into account, it's safe to say that Celtic made the right call in cashing in on the player when they did, as his value has decreased with every season gone by.

Also, with Celtic currently having the best defensive record in the SPFL under Ange Postecoglou, it doesn't seem likely that many Bhoys fans will have been wishing they still had Matthews in their side.

AND in other news: Postecoglou must now unleash £10.5k-p/w Celtic “solider,” he could be a game-changer