Neil Harris admitted he was disappointed with his Millwall side’s performance despite earning a 3-1 victory over AFC Fylde in the FA Cup first round.

The Lions had to wait until the 54th minute to break the deadlock against the National League North side, in-form forward Aiden O’Brien poking the hosts in front.

Lee Gregory and a late Steve Morison strike assured the win at the Den, and Harris insisted he knew it would be difficult against Fylde, who had won their last nine games.

“I’m disappointed with some of our play and certainly disappointed not to have a clean sheet,” he said.

“I knew it was going to be difficult, I’ve seen them, I know what a good team they are and how difficult they would make it for us.

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“We had prepared the players for it.”

The win stretches Millwall’s unbeaten run to seven games in all competitions, but Harris conceded his side made it difficult for themselves.

He said: “Sometimes those games, and I’ve played in those games, until you get the first goal it’s difficult.

“Once we got the first one the second one came quickly, but then you have to be professional after that and we gave a really poor goal away, a really poor goal.

“I’m really disappointed with it, we could have made it a lot easier for ourselves.

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“You have a wobbly ten minutes when you think of the next goal, and it took its time coming for us.

“At 2-0 we should have been comfortable.”

The manager hailed the impact of substitute Aiden O’Brien, who was last week named League One player of the month.

“When you can bring the best player in the league for the last month on, it makes a big difference,” he added.

“We didn’t have a sparkle today, we weren’t proactive enough.

“I’m delighted to get through though.”

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Despite naming a strong team for the cup clash, Harris was pleased he could give certain squad players a run-out, including Paris Cowan-Hall and David Forde.

“That’s his [Cowan-Hall] first start in a Millwall shirt, he’s been here 11 months, I think that says it all,” he said.

“He’s had a stop-start time and he looked like he lacked a little bit of rhythm and knowledge to our play because of the minutes he’s missed.

“Jordan’s [Archer] done really well, to have two keepers of that quality, I’m really lucky.

“It was important that Fordey gets those minutes and keeps focused to play when needed.”

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