Tony Dobbin was today hoping to return to action towards the end of next month after suffering arm and shoulder injuries in a heavy fall at Doncaster on Monday.
His mount Breath Of Scandal fell six out when holding every chance in the Tote Exacta Coming Soon Chase.
The rider, who was thrown on to the turf, was attended by paramedics, who put a neck brace on him. He was then taken to Doncaster Royal Infirmary.
It was later confirmed he had a fracture high up on his left arm and had dislocated his left shoulder but he was not detained overnight.
"I'm struggling a bit," Dobbin said today. "I was knocked out for a while _ two or three minutes - in the fall and my head is bouncing this morning.
"The dislocation means I'm out for an automatic four weeks but I hope to be back after that."
Dobbin, 27, who will visit Carlisle-based consultant Hugh Barber later today, said: "I've brought my X-rays from Doncaster with me and I'm going to see Mr Barber to see how long he thinks I should be off for."
He is in fifth place in this season's jump jockeys' championship with 48 winners, making him the leading northern-based jockey, and is disappointed at the prospect of missing some choice mounts in the near future.
He said: "Things were going really well and I'm absolutely gutted to be injured at this time of year. I'll miss The Grey Monk at Haydock on Saturday and other good rides."
His greatest success to date came on Lord Gyllene in the 1997 Martell Grand National.
