Robert Shapiro did almost nothing at trial, same for F. Lee Bailey.
It was Barry Scheck that won the case for O.J. He twisted up the D.A.'s blood evidence into something that the jury didn't trust. He was masterful and the only one involved that is still successful to this day.
The D.A. also really fucked up by putting a hopeless woman and inept token in charge of the state's case.