The son of prominent Western Australian businessman and politician Max Evans, Evans had a late start to his swimming career, making his debut at the Australian Championships in his hometown of Perth, aged 17. Despite placing second in the 100 m breaststroke, he was not selected for Australia, and instead travelled to the United Kingdom to train under David Haller. During this period, he quickly improved his times and rose from outside the top 200 into the top 25 in the world rankings. Evans returned to Australia in 1980 and qualified for the Olympics in both the 100 m and 200 m breaststroke. A sprinter, he won the 100 m in an Australian record time and showed a preference for shorter events, which required less training mileage. Evans gained a reputation for often doing fewer training laps than his coach asked of him. Having rebuffed Australian government pressure to boycott the Moscow Olympics in response to the Soviet invasion of Afghanistan, Evans won bronze in the 100 m breaststroke. His career peak came in the 4 × 100 m medley relay, when he outsplit his opponents in the breaststroke leg of the relay, bringing Australia into contention for its eventual win, which remains the only time that the United States has not won the event at Olympic level.