Thomas Muster spent a few weeks after the 1st April 1989 in despair, thinking his career was either over or would never be the same again. His coach, Ronnie Leitgeb, had a specially designed chair made for him, and convinced Thomas to get back on court hitting balls using the chair, and that he'd soon be back on the tour giving everything he's got. Muster was convinced, and threw everything into his rehabilitation and comeback. It's amazing what Muster was able to do from April 1989 to December 1990. He was fanatical about getting over the injury, hitting balls, getting fit, getting back on the tour, and then winning big clay tournaments, big Davis Cup matches etc.
Leitgeb once said of Muster "He's lazy, until you convince him to do something. Once you do, he is fanatical about doing it with 100% desire and enthusiasm."