"The performance against Charlton really gave us confidence," says Harris
Neil Harris has urged his squad to battle through the remaining festive fixtures and enter 2017 with a foothold.
Millwall clawed their way within four points of the play-off places following Wednesday's victory over local rivals Charlton Athletic.
"That win has buoyed everybody," Harris told millwallfc.co.uk. "We are now on the same number of points as this time last year and we ended last season on a fantastic run. I expect the same now.
"The first half of the season has been a bit of a reality check but we have to be strong and build a platform for the second half.
"We will approach this one the same way that we approached the Charlton match, with desire, fight and passion."
The Robins travel to The Den in 19th position having not won a match in League One since November, but the Millwall manager believes their 'unpredictability' makes them a dangerous prospect.
"Swindon are one of those teams that you never really know quite what you are going to get. They can be outstanding or not quite at the races.
"They are a young side with some attacking purpose to them. They have dangerous players and we have to keep them quiet today and when chances come along we have to be ruthless," he added.
Neil Harris is expected to have a fully fit squad at his disposal while Luke Williams is likely to shuffle his squad for today's tie. Defender Brandon Ormonde-Ottewill and striker Jon Obika will be assessed prior to kick off, while James Brophy has been ruled out with injury.
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