Entering that encounter on the back of seven games without victory, the German head coach's side defied all the pre-match odds by recording an emphatic 2-1 victory over Jose Mourinho's men.
And with the Terriers on a similar run of poor form heading into Tuesday's clash (this time six league games without a win), Wagner is hoping a good result against the Reds will kick-start a campaign which has stuttered over the past month.
“We have to focus on ourselves – we expected we would lose some games,” David Wagner said.
“Of course it is something we do not want to happen - we've had similar periods in the past and turned it around because we remained focused on ourselves.
“This is exactly what we have to do now and it's a great opportunity in front of our home crowd tomorrow night.
“We should not get too carried away after this period of not getting the results that we wanted.”
“When I saw the Swansea City game I saw similarities to the game in which we beat Manchester United,” remarked Wagner.
“They scored the first goal, they were really on it and up for the fight, the crowd was there and of course, Liverpool were maybe not at their best.
“We had the same circumstances against Manchester United.
“The West Bromwich defeat now means Liverpool have lost two games in a row and look vulnerable at the minute.
“Does it mean we will be successful against them too? 'No'
“Does it mean we have a chance? Absolutely and we will try to grab it with both hands."
Although Liverpool recorded a comfortable victory at Anfield in the corresponding fixture earlier in the season, Wagner argues there are fine margins between winning and losing Premier League games – with individual mistakes costing his side dearly.
“If we play games against every opponent without making easy mistakes we have a real chance,” Wagner said.
“This was the case against Liverpool when we conceded shortly after half-time from an avoidable individual mistake.
“It is probably the headline for us throughout the entire season so far - if we are able to avoid these mistakes then we are competitive and very often able to collect points.
“It was also the biggest difference against Manchester United – we didn't make big individual mistakes.
“We have to make sure we are mentally strong enough to be focused from the first to the last whistle as individuals and as a group.”