The Tony McEvoy-trained Mouro will be aimed at Group One riches in Sydney after doing it the hard way in winning the Eclipse Stakes at Caulfield.

After being slow out of the gates, Mouro, with Damien Oliver aboard, worked overtime in the run.

In fast-run 1800-metre race, Mouro, the $3.60 favourite, went neck and neck with St Gabriel with the pair at one stage five lengths ahead of their rivals.

A relieved McEvoy said the Sale Cup winner has the makings of a Group One horse and will test that theory in either the $3 million Doncaster Mile or the $4 million Queen Elizabeth Stakes over the autumn.

"I enjoyed the last 100 metres only," McEvoy quipped.

"I've thought of him as a Group One horse for a long time and I suppose you have to find out."

He said Mouro was shaping as a 2000-metre horse but would have to race better than he did on Saturday to get the distance.

"He's a headstrong horse and when things go smoothly for him it's fine, but when they don't he takes control of it," McEvoy said.

While St Gabriel faded to the back of the field, Rain Drum ($3.70) closed late to finish a half-length second with Bel Thor ($5.50) third, 2-1/2 lengths further back.