A drop in class has helped Encosta Line snap a seven-month absence from the winner's circle at Flemington, leading in a Chris Waller stable trifecta in the Grampians Region Handicap.

Encosta Line had Damien Oliver back aboard in Saturday's 2000m benchmark-78 race for the first time since the champion jockey guided the gelding to his most recent win in the same grade at Sandown last November.

The win also brought up a winning double for the Waller stable at Flemington after three-year-old filly Overstep won the Barwon South West Region Handicap (1100m).

After settling just worse than midfield with cover in the running line, Oliver produced Encosta Line at the right time in the straight before fighting out the finish with stablemate Sayed.

Encosta Line ($7) got the better of Sayed ($7) by three-quarters of a length on the line while fellow stablemate Xebec ($61) grabbed third, another 2-1/2 lengths away.

Oliver has won on Encosta Line in his only two rides on the four-year-old gelding.

"I think the drop back in class from a benchmark 90 last start suited him," Oliver said.

"He had a nice run, joined in nicely at the top of the straight and won well."