Charlton Athletic manager Karl Robinson says he must take the blame after Arsenal youngster Stephy Mavididi was stretchered off with a hamstring injury on Saturday (25 February).
Eighteen-year-old Mavididi joined the League One side on the final day of the January transfer window and has made five league appearances to date, starting the last two games.
The Addicks suffered a home defeat to League One strugglers Bury on Saturday with the Arsenal starlet a late casualty. His side were forced to finish the match with 10 men, having already used all of their permitted substitutes.
Speaking after the match, Robinson admitted he had expected too much too soon from a young player still getting to grips with senior football. He was quoted as saying by London News Online: "I've got to take responsibility. I apologise to Stephy, I let the emotion of the result get in the way of the development of a player.
"It's my fault he got injured. I'm sick as well, because I know working with young players that once you have an increase in loading period then two-and-a-half games is probably the maximum amount of loading you can do when you've not played first-team football before.
"Because he has been so good we have become reliant on him and I've got carried away with how well he's been doing, rather than how much I need to protect him.
"I have to apologise to the boy, I should have been stronger and taken him off sooner."
Neither Charlton or Arsenal are yet to comment on the severity of the injury but the League One side have confirmed he will not be available for Tuesday's trip to Shrewsbury Town.
Mavididi was named on the bench in Arsenal's two EFL Cup fixtures earlier this season, but is still to make his senior debut for the club.