Millwall manager Neil Harris believes his side are in for a 'difficult game' when Leeds United travel to The Den on Saturday.
Marcelo Bielsa's men top the Championship table after six games and are yet to suffer a defeat with early talk of a return to the Premier League beginning to gather momentum.
The Lions were one of the surprise packages last season, finishing just three points outside a play-off spot despite having just been promoted from League One.
However, Harris' side have began the campaign poorly, dropping to 17th in the table following a run of three consecutive defeats. But nevertheless, Millwall are strong at home, losing just twice The Den since November last year.
And on their previous visit to Millwall, Leeds know all too well about The Lions' toughness after losing 1-0 courtesy of a Aiden O'Brien strike, almost exactly one year to the day on Saturday.
Harris has called for Millwall to be 'resolute' and said they need to get back to being 'really nitty-gritty' for the visit of Leeds.
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“Leeds is a really difficult game," Harris told South London Press.
"we need to try to be that hard-to-beat and resolute Millwall team. It is just finding that again and ironing out a few things that have let us down in the last couple of weeks
"We have got good players and a good team. The harder you work the more rewards you get in the game.
“We’ll be working really hard over the international break. There is no guarantee of winning a game of football but it is about getting back to being really nitty-gritty and at our best.”