The Willie Mullins-trained Monkfish is out for the season after a setback while stablemate Min has been retired.
The former took all before him in his first season over fences, winning the Neville Hotels Novice Chase at Leopardstown, the Flogas Novice Chase at the Dublin Racing Festival and the Brown Advisory Novices' Chase at the Cheltenham Festival - all Grade Ones - in superb fashion.
He was beaten by high-class mare Colreevy when sent off the 10/11 favourite for the Champion Novice Chase at the Punchestown Festival but the Susannah Ricci-owned horse was the joint 6/1 favourite for the Cheltenham Gold Cup in March.
The trainer told sportinglife.com: "Unfortunately he has an issue with a tendon and it requires the season off.”
Meanwhile Min is heading into retirement after a sparkling career.
He won seven Grade Ones in Ireland and England including three John Durkan Chases at Punchestown and the 2020 Ryanair Chase.
The trainer added: “He suffered an injury in this year’s Ryanair which we operated on. We were hoping to get him back for this season but unfortunately it hasn’t come right for racing but he’s heading to a very good home to make an excellent riding horse for them.
"He gave Susannah and Rich and the team here some wonderful days over the years, including the win at Cheltenham, and was a tremendous horse."