Millwall manager Neil Harris says Middlesbrough have underachieved so far this term.

Boro, who were one of the pre-season favourites to make an instant return to the Premier League, are eighth in the Championship.

Despite spending over £40m on new players, Garry Monk’s men have struggled to put a run of form together.

Harris, whose Millwall team host Middlesbrough on Saturday, believes the Smoggies should be challenging for automatic promotion.

He told News Shopper: “They’ve probably been a little bit inconsistent. They had a really good start then tailed off a bit and then they won some games, lost a couple and came back with a good win and performance last week.

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“So, what’s not lost on us as a group is that they spent £46m in the summer. So there’s absolute quality throughout their squad, certainly in the attacking areas.

“It’s a side that have underachieved being eighth in the division, massively underachieved.

“They should be comfortably in the top six if not top two.

“It’s easy to say that because they’ve spent a lot of money they should be top of the league. It doesn't always work like that in football.

“Sometimes you build small steps to build for the future. Boro have spent big money to recruit personnel that are established at this level. That’s what makes them such a difficult opponent.”

Harris is expecting Middlesbrough to dominate possession at the Den.

News Shopper:

Neil Harris | Picture: Benjamin Peters Photography

And he has asked Millwall fans to be patient with his side as they look to knock off another big club in SE16.

Harris added: “We know it’s going to be a test - they’re a dangerous away side. They've got a massive amount of pace on the counter-attack.

“It’s going to be another game where a team will come to the Den and try to keep the ball.

“With our next two home games against Middlesbrough and Wolves - it’s going to be like another Reading and Sheffield United to a certain extent - where they have a lot of the ball.

“We’re going to have to be patient and we’ll need the crowd to be patient with us and encourage the players to do what they're good at.”