A Jermaine Easter goal on the half hour was enough to separate the two sides in what was a tempestuous encounter at The Den.
In a game that featured two brawls, tempers flared early on when Alan Dunne went in with a late, mistimed challenge that Lions’ boss Holloway thought was worthy of more than the yellow card Dunne received.
“If that’s not a red card I don't know what is!” Holloway revealed.
“I don't know what Dunney was thinking, I could see he was trying to stop the bloke getting through, it was pretty cynical.
“The referee handled it well, they went over the top, because he wasn't hurt.
“That set the tone for the rest of the night, to be fair it made it quite interesting.
“I’m sure if the FA were watching we would have been fined a little bit and they might have been too, but it’s just Millwall, it’s great.
Holloway fielded two different teams each half as the Lions finished their pre-season schedule unbeaten and the Den boss feels practice is making perfect after Friday night’s victory.
“I’m pleased with what we've been practicing,” Holloway said.
“I could see it out there, and I could see it in both teams.
“I’m a little bit disappointed we've only got one goal, there were some great crosses into the box and there was some good play and that’s the first time those particular teams have played together.
“We had the players in training this morning, so they're playing off a tired base, they've come out and gone again and I think they feel great, really feel sharp and they felt good.”
“I ran them the day before and did one of my times and they'd all beaten it by at least three or four seconds, they felt they had recovered really quickly.”
Holloway added: “The confidence you could feel and see around the ground with some of the things we did I was pleased with.
“I’m really pleased we managed to get a Spanish team over, I love how they keep the ball.
“They were a good test for us and they were away from home and trying to pass it.
“I felt, particularly in the first half, we closed, pressed and caused them all sorts of issues without the ball and that’s what were going to need to do better. We didn't look like letting a goal in.”
During pre-season Holloway has used the time to further teach his players his footballing philosophy, and it looks to be paying dividends with the season only days away.
“We looked like we were confident,” Holloway explained.
“I thought we showed immense discipline as well, it could have easily fired up, particularity that last bloke. I got involved and he said something to me, I think it was ‘have a nice day!’ “It’s all about structure, it’s what you want to try and create, I want to create something here that's very difficult for anybody.
“Hopefully we wont have to change, but we will be able to change, if I'm boxing someone and he suddenly switched to southpaw, I've got to be able to adapt and overcome, we will have to do that.
“I want us to be able to do things, hopefully we won’t ever worry about anyone else, we will just keep doing what we do. I think the lads are buying into it.”