Jonathan Edward Myers was stopped by staff at Flannels in the Strand Shopping Centre as he tried to walk out with it.
The 40-year-old also asked, via his advocate, for a second offence, of theft from Boots, to be taken into consideration during sentencing.
He will be sentenced on December 13 in summary court after a probation report has been completed.
Myers was subject to a suspended sentence at the time of the offence, imposed in March for stealing Smart toothbrushes and a Braun shaver from Boots the chemist.
Prosecuting advocate Hazel Carroon told the court that Myers, who lives at Glashen Terrace in Ballasalla, entered Flannels on August 13.
He was recognised by staff due to being on a Shopwatch list, a scheme that shares information between stores about potential shoplifters.
Myers was seen carrying a Canada Goose coat, valued at £1,150.
The security tags had been taken off the coat and staff challenged Myers and took the coat from him.
He left the store but CCTV footage was viewed later which showed Myers removing the security tags and putting them in a shoe which was on a shoe display.
Myers was arrested in Strand Street and when interviewed at police headquarters, claimed he could not remember the incident.
After being shown the CCTV footage, he then claimed the door alarm kept going off for no reason but still denied trying to steal anything.
He said staff had asked him to leave the store because he was on the Shopwatch list.
Ms Carroon said that the coat had been damaged when Myers removed the tags and was put back on sale at a reduced price, but no compensation request had been received.
Defence advocate David Reynolds asked for a probation report to be prepared before sentencing and said that Myers was currently receiving support from the Drug and Alcohol Team, whose input would also be beneficial.
Bail continues in the sum of £500 with conditions to contact probation services and not to enter the Strand Shopping Centre.