[1] Neall's father cited his daughter's personal trait of wanting to prove her sceptics wrong as a major attribute in her future success.

He took her to Arthur Cusack at Brisbane's Centenary Pool, and only two weeks later, she came third in the under-9 division of the 50-metre freestyle at the State Schools Championships.

[1] Soon after, the family moved back to Sydney, and Gail began to swim under Harold Reid at the Frank O'Neill pool at Pymble, New South Wales.

[1] Neall quickly encountered success, winning her first New South Wales Championship in her age division of the backstroke at 11 in 1966.

She returned in the 1969 New South Wales Winter Championships, where she did well enough to win selection for a state team tour of New Zealand.

In Edinburgh, Scotland, she claimed a silver medal in the 400-metre individual medley, finishing more than five seconds behind fellow Australian Denise Langford.

[1][2] Neall continued her rise after the Commonwealth Games by winning the medley double and a silver medal in the 200-metre butterfly at the 1971 New South Wales Championships.

She finally broke through for her first title at the 1971 Australian Championships in Hobart, taking the 400-metre individual medley in a time of 5 m 16.5 s.[2] In 1971, she switched to the coaching of Don Talbot at his Hurstville squad, after her parents became increasingly uncomfortable with Carlile, perceiving that he did not have confidence in her ability to win at the highest level.

Neall's father felt that his daughter's performance improved as a result of Talbor's individual attention to his swimmers, thereby building their confidence.

[3] Neall was considered an outsider in her pet event, the 400-metre individual medley, with Americans Jennifer Bartz, Lyn Vidali and Mary Montgomery, and Canadian Leslie Cliff fancied to take the gold medal.

Despite being expected to falter in the breaststroke, Neall managed to maintain parity, and still narrowly led at the change into freestyle with a split of 3 m 55.51 s, having repelled attack by Cliff and Bartz.

Cliff attacked in the first half of the freestyle leg and took a narrow lead at the final turn, before Neall fought back to draw level with 30 metres to go.

[5] In the final, she was unable to challenge the winner, Karen Moe, from the United States, who broke her own world record.

[5] She was a schoolmate of fellow Munich gold medal winning swimmer Shane Gould at Turramurra High School on the north shore of Sydney.

The selectors persisted with her and chose her for the International Coca-Cola Meet in London and the World Championship in Belgrade, Yugoslavia.

Although she won a bronze in the 200-metre butterfly in 2 m 21.66 s, her performance in the 400-metre individual medley was 10 seconds slower than her personal best, and left her last in the final.