Dan Cassidy is the former physical therapist for the Oakland A's Baseball Team for 4 seasons from 1993-1996. Previously, he was the consultant for the San Diego Padres from 1990-1993. He is currently a consultant for the United States Tennis Team.

Dan received his physical therapy degree from Northwestern University Medical School 1987and majored in Mechanical Engineering at Southern Illinois University at Carbondale from 1983-84. He also studied and majored in Theology and minored in Business at Franciscan University of Steubenville from 1997-1999.

His baseball playing experience began at Southern Illinois University at Carbondale from 1983-1984 where he played shortstop for the 1984 Missouri Valley Conference Championship Team. He also had a short stint with the New York Mets minor league organization in 1986.

His coaching background includes two seasons as a volunteer for the University of San Diego WCC Champions 2001-2002 Baseball Teams, and for the Semi-Professional San Diego Barona Stars who won the Grand Forks International Baseball Tournament in 2004. He currently coaches for the Santa Fe Christian High School Baseball Team, CIF runner up champions 2006.

Dan runs his own physical therapy practice in Solana Beach California and also lectures on shoulder rehabilitation and conditioning for physical therapists, physicians, athletic trainers and strength coaches. Dan has lectured for the American Baseball Coaches Association, the European Baseball Coaches Association, the National Strength Conditioning Association, the Professional Baseball Athletic Trainers Conference and for Japanese Medical and Baseball Professionals. Dan has revolutionized the science of rehabilitation with the invention of the AB & BACK 2000. This new machine allows for remarkable strengthening of the abdominals and lower back.