Ruddock admits his team were hurting after the show at Vicarage Road and after a week of training is confident a response is coming from his team at The Stoop.
"We didn't play to our standard at Saracens last weekend and we are looking for a reaction," he said. "We felt we were making progress week-to-week but ultimately we let ourselves down last time out and need to put it right.
"We have spoken about playing ball in hand rugby and when we string phases together we look a good team. Perhaps sometimes we don't go out there and adopt enough ambition. We now need to commit to taking the game to Quins, we plan to be positive."
Harlequins secured a closely fought 10-7 victory at Sixways when the two teams met at Sixways in December.
But Ruddock is convinced the lessons of that day have been learnt.
"There form has been indifferent but they were very physical when they came to Sixways and looked to bully us up front, that doesn't usually happen to us," he said.
"We need to go back there and return the favour and take it to them up front."
Worcester have already tasted success at The Stoop this season after victory in the EDF Energy Cup in November - a first competitive win for the Ruddock era.
And thew Warriors chief believes that memory can spur his side towards another famous result.
"We have been to The Stoop and won this season in the cup. That means we can go back and be confident we can beat this team," he said.
"We have spoken about that display in team meetings this week, we beat them there when they had a good team out and now we need to repeat that.
"We are all hurting from what happened at Saracens, we were going through a transitional period earlier in the season but there are no excuses now. We need to perform and we need to play to our potential to get the result we need."