Nicky Henderson has announced Mark Walsh will ride Jonbon for the first time in Saturday’s bet365 Celebration Chase at Sandown.
Meanwhile, James Bowen is in line to partner Constitution Hill if he is given the “double green light” to run at the Punchestown Festival next week.
With stable jockey Nico de Boinville sidelined by injury, the Seven Barrows handler is having to make alternative riding arrangements for his two stable stars.
Speaking in his Unibet blog, Henderson said: “Firstly I want to say thank you to everyone for their thoughts and kind messages following Nico’s fall, which we have passed onto him. He is now back at home and will need to rest. We don’t know exactly when he’ll be back riding but we wish him a speedy recovery.
“In the meantime we do have to make riding plans for our horses and Mark Walsh will come over to Sandown Park on Saturday to ride Jonbon.”
Having gone unbeaten in his first 10 career starts, Constitution Hill has suffered successive falls in the Champion Hurdle at Cheltenham and the Aintree Hurdle.
Henderson has left open the option of a first trip to Ireland for the Punchestown Champion Hurdle, but a final decision on his participation has yet to be made.
He added: “Constitution Hill has an important gallop on Friday and he will be partnered by James Bowen. If that goes well they will school together over the weekend and if we get a double green light so to speak, then we can all head over to Punchestown. Everything hinges on how this weekend goes.”
The trainer could also send his star juvenile Lulamba to Ireland’s end-of-season meeting, saying: “Lulamba is in great form and could also head over. It’s a brave shout but I’m very happy with him and James would also take the ride if we line up.”