Paris Saint-Germain's Champions League clash with AC Milan this week will see the French club come up against one of the many outstanding talents they have let slip away in recent years.

In the Italian side's goal will be Mike Maignan, who was allowed to leave Paris for Lille in 2015 and has gone on to win a Ligue 1 title, Serie A and become France's first-choice 'keeper.

PSG, meanwhile, handed the gloves to a long list of goalkeepers before signing Gianluigi Donnarumma from Milan in 2021 and making him their undisputed number one a year later.

But would the Qatar-backed club have ultimately been better off keeping faith in a young Maignan than going from Salvatore Sirigu and Kevin Trapp to Gianluigi Buffon, Alphonse Areola, Keylor Navas and then Donnarumma in their ongoing quest to win the Champions League?

Now aged 28, Maignan has become one of the world's outstanding goalkeepers and will be Milan's last line of defence against his France teammates Kylian Mbappe, Ousmane Dembele and Randal Kolo Muani in a pivotal Group F match.

Having kept clean sheets in draws with Newcastle United and Borussia Dortmund so far in the group, Maignan is set to return for Milan after sitting out the 1-0 Serie A loss against Juventus on Sunday due to suspension.

"It is always a strange feeling to go back home, whether that to be to Lille or Paris," said Maignan while on France duty last week.

He missed last year's World Cup with injury but has become France's first choice since Hugo Lloris retired.

"It brings back memories. I have already played against PSG for Lille. It's the Champions League. There will be a great atmosphere. My family will be there. I need to make sure I focus on my job and not let the emotions overwhelm me."

There has been much focus in recent months on PSG's lack of Champions League success while their Qatari owners have adopted a policy of spending huge money on superstar signings.

Meanwhile they have rather neglected the young talent on their doorstep in the fertile football breeding grounds of the Paris region.

A conscious effort has been made to change the approach with the departures of Lionel Messi and Neymar and the arrivals of exciting French talents like Normandy-born Dembele and Kolo Muani, a native of the same Paris suburb as Mbappe.

It is not just Maignan they let go over the last decade, with Kingsley Coman, Adrien Rabiot, Christopher Nkunku and Moussa Diaby all choosing to pursue their careers elsewhere.

As well as Maignan, the Milan side to face PSG could include Yacine Adli, a 23-year-old playmaker born in the Paris suburbs who left his hometown team after just one top-team appearance.

PSG have won just four two-legged knockout ties in the Champions League since Maignan left eight years ago.

"That means nothing to me," Maignan said last season in a post-match interview when asked what he thought about PSG going out of the competition against Bayern Munich.

Having slumped to a 4-1 defeat in Newcastle three weeks ago, a failure to beat the "Rossoneri" on Wednesday would increase the risk of Luis Enrique's side not getting out of their group, which would be disastrous for a club of PSG's ambitions.

Questionable recruitment decisions have cost PSG in recent years, like allowing a 20-year-old Maignan to join Lille for a reported one million euros ($1.1m) in 2015 having never played a top-team game.

Born in French Guiana, Maignan was eight when he moved to mainland France with his family. He joined the PSG academy in 2009.

"PSG practically threw him out, like they have done with others. You wonder what the club's policy is," former Paris and France goalkeeper Bernard Lama told sports daily L'Equipe earlier this year.

"They should have loaned him to Lille. If he stands out, then you bring him back instead of going out and buying someone else and getting it wrong."