Mingi played 72 minutes as Charlton's Under-23s beat Burnley 3-0 at The Valley on Tuesday afternoon.
U23S | The Addicks finish their season by hosting @BurnleyOfficial in SE7 this afternoon.— Charlton Athletic FC (@CAFCofficial) 16 April 2019
Here's how we line up
XI | Maxwell, Yao, Mingi, Vega, Page, Morgan, Odoh, Forster-Caskey, Doughty, Kalinauskas, Aouachria.
Subs | Harness, Keefe, Stevenson, Ocran. #cafc pic.twitter.com/7dFTetABOc
The 18-year-old's two-year scholarship contract expires this summer and he appears to be on his way out of West Ham.
But whether he's impressed enough to earn a deal with the Addicks remains to be seen, after giving away a penalty from which Daniel Agyei hit the crossbar.
Mingi joined West Ham at the age of seven and progressed all the way through to U23 level.
Goals from Alfie Doughty (two) and Abraham Odoh secured the win in what was Charlton's final game of the U23 season.
The past-and-present West Ham players, Lewis Page and Josh Cullen are currently under contract and on loan at Charlton respectively.
Page continued his comeback from injury alongside Mingi earlier.