Manchester City's academy continues to be a valuable money making tool for the club.
It has established itself as one of the best academy setups in the country and its production line is one that other clubs will look at with envy.
In an era where pure profit for selling academy graduates is vital as clubs combat the Premier League's profit and sustainability rules, those sales have been huge for City being able to spend and improve their squad.
The dream, of course, is that City's youngsters progress into and establish themselves as first team players like Phil Foden, Rico Lewis and Nico O'Reilly.
But a number of City youngsters have been sold on for healthy profits and thrived elsewhere. Cole Palmer, Liam Delap, Taylor Harwood-Bellis and Morgan Rogers are chief among them.
But what City have also been excellent at is installing sell-on clauses into those sales which means they profit down the line, too.
Last summer City sold Tommy Doyle to Wolverhampton Wanderers after a successful loan spell at Molineux.
However, the former England under-21 international fell out of favour after Vitor Pereira replaced Gary O'Neil as manager.
As such, he has joined ambitious Birmingham City, who are part-owned by NFL great Tom Brady, on a season-long loan deal.
"I'm really excited, it's a big club with big ambition, so I'm looking forward to getting involved and getting down to work," Doyle [told Birmingham's website](https://www.bcfc.com/pages/en/media-article/tommy-doyle-this-is-a-big-club-with-big-ambition) after joining the club.
"The way the club is going about its business is really impressive and it shows that the club is only going one way."
The Blues are targeting a second successive promotion and a return to the Premier League and are expected to be aggressive in the transfer market.
Should they make that loan deal into a permanent deal, City are said to have a 50 per cent sell-on clause on any future transfer.
They will be watching the 23-year-old's progress at St Andrew's with a keen interest this season.