Give Famous Seamus an inside barrier and a firm racing surface and his bona fides as a Group One sprinter are rarely in doubt.

In the $2.5 million TJ Smith Stakes at Randwick on Saturday, Famous Seamus has one but not the other and trainer Noel Mayfield-Smith can't believe his luck - or lack of it.

Famous Seamus will jump from barrier three but Randwick was rated in the heavy range before a minor mid-afternoon upgrade on Thursday.

News of Randwick's improvement will boost Mayfield-Smith's confidence despite bookmakers writing off Famous Seamus' chances against Exosphere and Chautauqua.

"If you sit down and analyse his form and go through and see the bad runs, or what appear to be ordinary runs it will show you he had a wide gate or was it a wet track," Mayfield-Smith said.

A Group One BTC Cup winner, Famous Seamus will be making his third appearance in the TJ Smith after soft conditions put paid to his chances in 2014 and 2015.

The seven-year-old will be ridden in a race for the first time in his 46-start career by Glyn Schofield after James McDonald had the mount in the Galaxy.

Famous Seamus finished at the back of the field but Mayfield-Smith insists there was hidden merit in the run.

"It was acceptable from the point of view that he didn't handle the track because when they came out of the chute, apparently it was very chopped out," he said.