This article forms part of our Profit Players feature series, which is where Football Transfer Tavern takes a look at how well a player has fared since being signed or sold, using statistical figures and statements from pundits to prove how good of a deal the club managed to achieve.

As Paris Saint-Germain made the Champions League semi-finals after beating Atalanta on Wednesday, they were helped by one former Everton player.

The French side prevailed against the Serie A club following a dramatic end to the game - they were 1-0 down going into the 90th minute before goals from Marquinhos and Eric Maxim Choupo-Moting completed an unlikely turnaround.

Idrissa Gueye was included in the PSG starting line-up in Lisbon, with the Senegal international making the switch to the Parc de Princes in July of last year for a fee of £29m following his impressive performances for the Toffees.

In 2016, Everton paid £7.1m to Aston Villa to take him to Goodison Park. The Villans were relegated to the Championship prior to the move but Gueye was one of the Midlands club's standout performers as he managed an average WhoScored rating of 7.25 in the Premier League during the 2015/16 campaign.

Throughout his time with Everton, he was a consistent player - he averaged a rating of over seven in two of the three campaigns he had on Merseyside and would make 108 appearances in all competitions for the club. Not only that, he also averaged more than 3.5 tackles per match during his spell with the Toffees.

Ronald Koeman may have only managed one year with the Toffees before moving on, sacked with them in the relegation zone in October 2017 amid criticism of "bringing an air of negativity to Merseyside" (as per Goal.com), but the signing of Gueye was an inspired decision.

His move to PSG ensured that Everton made a profit of £22m - that is an increase of 314% on their original outlay, which reflects that the Toffees did tremendous transfer business where the 30-year-old is concerned.

Everton fans, do you reckon Gueye was Koeman's best signing for the club? Let us know what you think in the comments below!