He would go on to attend UCLA. As a freshman at UCLA, Lewis had a spectacular year in 1988, when the precocious 19-year-old not only completely rewrote the world junior all-time list in the 400 m, but also proved his mettle in senior competition by winning the Olympic gold medal.
Lewis had not been a total unknown prior to 1988, having set a personal best of 45.76 at the 1987 USA national junior championships, but he caught many unawares when he won his quarter-final at the
world junior record of 44.61, and then slashed this time the following day, when he won his semi-final in 44.11. Despite this performance, Lewis could only finish third in the final in 44.37, having been well beaten by his older compatriots, Butch Reynolds and his UCLA teammate, Danny Everett
.
In the Olympic Games at
North American and World junior record. Steve won a second gold medal three days later, as a member of the victorious USA 4 × 400 m relay team which equalled the world record of 2:56.16 that had stood since the 1968 Olympics
.
By the end of 1988, Lewis had run what still rank as 7 of the top ten junior 400 metre races of all time.[2]
In 1992, Lewis, once again, competed at the Olympic Games in Barcelona and won a silver medal in the 400 m and a gold medal in the 4 × 400 m relay, which broke the world record (2:55.74) that Lewis had previously helped tie in the 1988 Olympic Games.
The rest of Lewis' career was affected by injury and an ongoing viral illness, and he never again competed at a major international championships.