The 20-year-old played in an advanced role on Friday evening and took the plaudits after impressing fans and management during his second half performance.
And Holloway has no doubts about the Republic of Ireland U21’s ability.
“He has to understand the importance of where he's got to be and that comes with maturity,” Ollie said.
“I need him to mature very quickly, ability wise I've got no doubts about what he can do and how he can do it.
“It’s about structure, team organisation, being serious enough about the place, being grown up and making the sacrifices he is going to have to make and be a proper player for us.
“And also how I want him to play under the guidance of Neil Harris.”
Holloway went to say that he has asked coach Des Bulpin to be more involved in Millwall’s youth set-up and revealed he is impressed with his youngsters attitudes.
He said: “Des Bulpun I've moved a little bit so make sure he tests everyone I'm getting in and he watches all the other U21’s and I compare them to the ones I've got.
“So no one is going to get a free ride at this club in the future.
“If I can loan one or two out and get them going and get them experienced, but I’m delighted with them.
And Holloway has also praised the atmosphere around the club ahead of the new season.
“I think the attitude of the place at the moment is what I want, and I've got no points and no games played, and I’m talking absolute twaddle but it’s something.
“If I believe if we get that right, the results will take care of themselves.
“It's coming, you only have to look at Scott McDonald and see how fit he looks and how up for it he looks.
“The camaraderie they've got, talking to Ricardo Fuller and it’s all very exciting and that's coming from the staff.
“It’s got to come from the staff and with the unit we’re going to create here and everyone understanding their job.
“Where we can finish and where we can end up, I don't think theres a limit on it, I swear to you.
“I’m really excited about it.”