Unai Emery believes Rob Holding has vindicated the club's decision to keep him at Arsenal this season.
The defender has started 11 of the last 13 games across all competitions and has developed into a key figure in Emery's first six months in charge at the Emirates Stadium.
Holding admitted recently that he was "disappointed" to miss out on the last England squad and is still targeting a debut senior cap.
The 23-year-old stayed put following Emery's arrival, while fellow centre-back Calum Chambers joined Fulham on loan.
Coupled with injuries to Laurent Koscielny and Konstantinos Mavropanos, Holding has seized his chance and appears to have impressed Emery along the way.
"We decided for him to stay here and when he had chances, he played well and he helped us with big performances," the Gunners head coach said of Holding.
"Every match is a test, another test for Rob to do that. He is improving, he is taking confidence and with confidence he is at his best.
"In the pre-season we also had Mavropanos – but he is injured now – we had also Chambers and we decided to let him go on loan to Fulham and we decided that Rob Holding stayed here.
"But in the pre-season, every decision was looking at the matches with the players and finding the best performance in this moment."
Holding's place may come under threat in the next few weeks as Mavropanos and Koscielny return from their respective injuries.
Club-captain Koscielny is stepping up his return from an Achilles injury he suffered in the Europa League semi-final defeat to Atletico Madrid in May.
Emery has not ruled out slowly introducing Koscielny back into action, starting with Monday's Under-23 fixture against Derby.
"The process with him is that in this International break, it is to finish training with us every day to start playing, little by little," he said.
"First, our idea is to start with the Under-23s, but also, these two weeks training with us, I am looking at him. He is well, with good performance, good feeling and I think he, today, is close to also play with us.
"But the first idea is, and maybe on Monday, he can play with the 23s. We are going to decide tomorrow the plan with him, but we are thinking for him to start to take minutes."
