Stuart Findlay believes it's important Hearts defenders contribute with goals during captain and top scorer Lawrence Shankland's absence.
The Scotland forward, 30, was last week ruled out for up to eight weeks with a hamstring problem.
Findlay, 30, scored Scottish Premiership leaders Hearts' first equaliser in Sunday's 2-2 draw with Celtic at Tynecastle.
Between Findlay and fellow centre-back Craig Halkett, the pair have contributed 12 goals so far this season.
"We've lost such a goal threat in Shanks for the next week while," Findlay told BBC Scotland. "We know that. We understand how much goals he brings to the team.
"But we know how much of a threat we've been at set-pieces. It's important we keep scoring. We've been a threat from these situations, which I thought we were again [against Celtic]."
Hearts lead Rangers by four points and Celtic by six. Victory away to Dundee United, where Findlay scored twice earlier this season, will open those gaps wider before Rangers visit Hibernian and Celtic host Falkirk on Sunday.
"We have to go into the game determined to get the three points, like we do every game," Findlay said.
"If you keep winning games, then you just sort of see what happens."
