FORMER Spreyton jockey Trent Wells will miss out on the chance to represent Australia in an international jumps series against Ireland after sustaining season- ending injuries in a race fall in Adelaide on Saturday.

Wells, 22, was riding Big Ego in the Cleanevent Grand National Steeplechase at Adelaide's Morphettville Raceway when his mount fell on the second last jump in the finish straight.

Wells was dislodged and sustained a broken collarbone and fractured thumb.

He will undergo surgery in Melbourne today to repair the damage to his thumb, but will take no further part in the Victorian- South Australian jumps season, which has about a month to run.

Wells was only last week selected to ride for Australia in the Australia v Ireland Jumps Jockey Series, conducted over four rounds in Victoria and South Australia.

"I'm bitterly disappointed," Wells said.

"I was getting very excited about riding for Australia so this has been a real kick in he guts."

Ironically, his injury could pave the way for another former Coastal jockey, Adam Trinder, to gain selection for Australia.

Selectors have yet to name a replacement for Wells, but Trinder, who has ridden in the series before, would be in the mix after a solid season this year.

Wells said his mount in Saturday's race was running well at the time of the fall and was not injured in the incident.

"We were going to finish second, but he just stumbled forward onto his nose when he landed after the second-last jump," he said.

Wells broke his pelvis three years ago in a trackwork accident, but said Saturday's incident was his worst actual racing accident.

It hasn't deterred him from continuing in what is obviously a dangerous sport.

"I'll be back next season."

The former Coastal jockey said he had received many phone calls and text messages of encouragement from home since his fall.

"I haven't been able to get back to all of them, but I would really like to thank all the people back home in Tassie who have been sending me messages," he said.

Before his accident Wells was enjoying his best jumps season to date, riding 15 winners and placing in a number of major steeplechase events, including second in the $202,000 Hiskens Steeple at Moonee Valley last month.

He also finished third in the Tom Corrigan Medal for jumps jockeys.