Manchester City took an early lead in Hong Kong when Antoine Semenyo burst down the left and squared for Divin Mubama to tap in from close range in the 14th minute, only for Inter Milan to level six minutes later when the visitors' defence failed to deal with a Jamal Iddrissou delivery and Benjamin Pavard fired home from close range.
Neither side could find a winner in front of more than 42,000 fans at the Kai Tak Stadium, and City went on to lose the resulting shootout 3-1, with Rayan Ait-Nouri, Abdukodir Khusanov and Nico Gonzalez all missing their spot-kicks as Inter claimed the Asahi Super Dry Trophy.
It was 18-year-old McAidoo who caught the eye most after replacing Mubama at the break, repeatedly getting the better of Inter's defenders and twice going close, rattling the foot of the post with one effort and seeing another drift narrowly wide.
The teenager arrived at City from Chelsea's academy two years ago and has already banked a senior debut and a goal in a 10-1 FA Cup romp over Exeter City under Pep Guardiola, but Saturday's outing in front of a new manager was arguably his most eye-catching audition yet.
"We have been speaking with the club about Ryan and since day one he is that kind of winger I love," Maresca said. "Very aggressive one v one, always trying, making the right decision. But he is young and he needs the right path."
Maresca fielded a host of academy graduates throughout the match, with Stephen Mfuni and Mubama starting before Max Alleyne, Mamadou Sangare, Kaden Braithwaite and McAidoo were introduced for the second half — with seven further young players held in reserve on the bench for City's remaining Asia tour fixtures against a K-League All Stars side and Atletico Madrid.
Speaking to the club's own Matchday Live afterwards, Maresca made clear how much the occasion meant to him.
"It's amazing, it's an amazing feeling," he said. "They are from the Academy. They are from the home. So it's nice for them. And also because they represent a little bit the fans and everyone. I was happy also with their performances so good."
Asked whether McAidoo and the other academy prospects could expect involvement in cup competitions this season or whether loan exits might be sanctioned instead, Maresca pointed to his track record of giving youth a chance.
"At the moment, with most of the young players, the idea was to see them in pre-season and then decide," he said. "We started 10 days ago. Ryan is working well, he just has to continue then we will take the right decision. I am always very open with the young players. When I was at Leicester, that season there was a record number of debutants. When I was at Chelsea, record debutants from the academy. If they are good, there is no problem."
On the performance overall, Maresca stressed that fitness rather than results was the priority at this stage of pre-season.
"We struggled a bit more first half but we knew the reason why," he said. "In the second half we were much better. In this moment, I think it's important the physical condition. In two weeks, we are already in an important game so it's good that they get better and better and better."