The letter comes after it was revealed that some coaches at Ellesmere College Titans Swimming club had been suspended by Swim England over “welfare and governance issues”.
The suspensions included the club’s director of swimming, Alan Bircher, a 10-time British champion and world championship silver medallist.
Mr Bircher has missed out on a role coaching at the Olympics as a result of the review.
The Titans, based at Ellesmere College but not managed by the college, have enjoyed huge success and a glowing reputation in recent years, producing a raft of international swimmers.
A number of former Titans have now signed a letter in support of the coach “and his colleague”, expressing their surprise at the suspension.
They include the European and Commonwealth medallist Freya Anderson, who will be making her Olympic debut at Tokyo, Hector Pardoe, also competing in Japan, and former British national champion Chloe Golding.
The idea for the letter came from former Titans Hannah Knight and Ms Golding.
In the statement the 73 swimmers praise the impact that the suspended coaches had on their careers. They describe Mr Bircher as “a coach who pushes us to be at our best” but “who makes sure you have a great time”.
Swim England has said the club will be subject to a number of review processes in the future – short, medium, and long term.
The swimmers’ statement said: “We are shocked and saddened to hear the news resulting in the suspension of Alan Bircher and his colleague from coaching at Ellesmere College Titans.
“As past and present swimmers of theirs, all training at Ellesmere College, we are confused as to how these allegations have come to light after we all had such amazing experiences swimming at Titans. Alan has given his life to swimming as an athlete, then as a coach. Without a doubt, he is one of the best coaches in Great Britain, helping so many of his athletes to compete on an international stage, most recently three to the Tokyo Olympics.
“None of us have ever experienced any hurtful or damaging behaviour from Alan and the coaches at Titans. We have only ever had the opposite – Alan is a coach who pushes us to be at our best, who makes sure you have a great time while getting there. He encouraged us to be open and helped us with any problems or issues we faced, many of us moved away from home as young teenagers to train with him and the Titans coaches are always the first to check on us.
“The opportunities that he has helped to provide to so many people are unmatchable, providing a fun, exciting and elite training environment. The Titans coaches affected by this decision are both hardworking individuals who only ever want the best for the young people in their care and do not deserve to be in the position they have found themselves in.”
Swim England, said it had taken action at the club after being contacted by parents concerned over “welfare issues”.