He reached the final of the 1991 European Open while ranked #59 in the world, a run which included a 5–0 win over Stephen Hendry; Johnston-Allen lost 9–7 to Tony Jones in the final. He reached the final of the same event again a year later, this time losing 9–3 to Jimmy White. He qualified for the World Championship in 1992, and lost 10–4 to Tony Knowles in the first round.