Grease on Pre-cast concrete

[GreenClean]

There is some grease from someone's hands on Pre-cast concrete. We have tried degreaser but it has not worked. We can not pressure wash because of the front door. Is there something else we can try in order to get the grease off the pre-cast concrete?
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[One Tough Pressure]

If you have already tried the typical degreasers and have not had any luck then I would try this. .: Degreaser : Klenztone 1 : Cleans Grease, Oil, Masonry Surfaces : K&E Chemical Company, Inc. - Surface Restoration Products, Klenztone (Interior & Exterior) :.

It is an ammonium biflouride based cleaner, so it is acid.