Police officers have launched an urgent appeal to find the two men believed to be responsible for the robbery at the Co-op on Barnsley Road at 7.40am on November 21.
A spokesperson for South Yorkshire Police said: “During the incident, one of the men threatened staff with a large knife.
“No-one was injured, but staff members were left distressed by what happened.
“CCTV images have now been released of two men that officers would like to speak to as part of their enquiries.
“If you recognise these men or have any information that might help, please contact 101.
“When you call, quote crime reference number 14/171849/20.”
Alternatively, you can stay completely anonymous by contacting the independent charity Crimestoppers via its website crimestoppers-uk.org.