The clock may be ticking for a man who allegedly duped two Gumtree sellers into letting him try on an expensive Rolex watch before running off with it.

Police are searching for the man who met the sellers at Doncaster Shopping Centre.

A Rolex watch, similar to the one that was stolen Credit:Victoria Police.

The sellers set up the meeting with the man, who used the name "Johnny", after he expressed interest in buying the Rolex Cosmograph Daytona watch, which had been advertised on Gumtree for $22,000.

After asking to try on the watch, the man ran off with it.