The Gulgong trainer was at Moonee Valley last night to watch his five-year-old gelding Slate On Edge run in his second race in Melbourne, before making the long journey back for Mudgee Race Club's event this afternoon.

Thompson has three runners competing at Mudgee's non-TAB meeting including Brooklyn Lad in the feature race of the day, the G.C Cox Plate.

Not to be confused with the $3 million Cox Plate at Moonee Valley, which will jump at 5.40pm, the G.C Cox Plate is only for a share of $6500 in prizemoney.

Last night Thompson was standing trackside at the Melbourne course, where he was hoping to celebrate his first interstate win with Slate On Edge in the Subzero Greys Challenge.

The Challenge has three races that visit racecourses at Caulfield, Moonee Valley and Flemington during the Melbourne Spring Carnival and Melbourne Cup Carnival.

Slate On Edge finished second at Caulfield last week and Thompson said the grey galloper pulled up well after his first run.

"He spent the week in Albury at Brett Cavanough's stables. Kurt [Brett's son] has been down here with him," Thompson said.

Thompson drove Slate On Edge back to Albury last night, and will jump in the car this morning with hopes of making back in time for Mudgee's first race at 2.35pm.

Thompson has runners in the first race with The Sea Lady, the third race with Boy OhBoy and the final race - the G.C Cox Plate - with Brooklyn Lad.

"Brooklyn Lad has started to hit a bit of form. As long as the track is not too hard he should run a good race," Thompson said.

"He is a stayer who has run 2000 metres. He is still a run or two away from his best but he will be up to the task."

Kandos trainer Greg Hook is the only other local trainer accepted for the G.C Cox Plate.

He will saddle up five-year-old chestnut mare Sobell Gaze for the mile race, which jumps at 5.10pm.