Strathclyde Police is appealing for information and witnesses following the incident last Wednesday evening.
Four men broke into the guard's hut near Morrison’s supermarket, assaulted him and bundled him into the back of a white van.
The gang then stole a JCB digger and made off in that and the van. They later crashed and abandoned the JCB near to Broadbent Farm, East Kilbride.
The guard was then driven in the back of the van a short distance before the suspects abandoned both him and the van near to Langlands Golf Course. They escaped in a red Seat Leon car.
Police officers arrived shortly after and found the abducted man in the rear of the van, with weapons nearby. He was taken to Crosshouse Hospital where he was treated for serious head injuries. Hospital staff said his condition was stable.
Detective inspector Paul Swinburne said: “This was a horrific and senseless attack on an innocent working man and I am determined to find the people responsible for this attack.
“After the suspects made off from the white van they got into a red Seat Leon with a partial registration believed to begin with SD07.
“I have no doubt that there were witnesses to this, as the suspects abandoned a white van, crashed a large JCB and made off at high speed in a red Seat Leon.”