1990: two-year-old season

Lycius recorded his first success in July 1990 when he won the Listed Prix Saint Patrick over 1400 metres at Deauville Racecourse. The runner-up River Traffic was later sent to race in the United States where he won the Laurel Futurity. On 9 September the colt was moved up sharply in class to contest the Group One Prix de la Salamandre over 1400 metres at Longchamp Racecourse and started at odds of 3/1 in a seven-runner field headed by the undefeated Hector Protector. After turning into the straight in fifth place he made steady progress in the closing stages to finish second, one length behind Hector Protector.^[6]

On 4 October Lycius was sent to England for the Group One Middle Park Stakes over six furlongs at Newmarket Racecourse and was made the 13/8 favourite in a nine-runner field. His opponents included Distinctly North (Flying Childers Stakes) and Majlood (Sirenia Stakes), Polish Patriot and Sylva Honda (Woodcote Stakes). Ridden by Cash Asmussen, Lycius was restrained towards the rear of the field as Distinctly North set the pace, before making rapid progress approaching the final furlong. Lycius overtook Distinctly North in the final strides and won by half a length with Majlood one and a half lengths back in third.^[7]

1991: three-year-old season

In all of his races in 1991, Lycius was partnered by Steve Cauthen. He finished second to the François Boutin-trained Ganges in the Prix Djebel at Maisons-Laffitte Racecourse on 12 April and was then sent to England to contest the classic 2000 Guineas over Newmarket's Rowley Mile on 4 May. Starting a 16/1 outsider he was restrained in the early stages towards the rear of the field before making rapid progress in the last quarter mile. He moved up alongside the leader Mystiko inside the final furlong but was unable to overtake the Clive Brittain-trained colt and was beaten a head into second place. There was a gap of six lengths back to Ganges in third, whilst the other beaten horses included Generous and Marju.^[8] Two weeks later, Lycius started favourite for the Irish 2,000 Guineas at the Curragh but was beaten into third place by the American challenger Fourstars Allstar and the locally trained Star of Gdansk.

Lycius was brought back to sprint distances for the July Cup over six furlongs at Newmarket. Starting the 11/4 second choice in the betting he finished strongly to take second place behind Polish Patriot with Elbio in third and Polar Falcon in fourth. On 11 August the colt had his first run in France since April when he contested the Prix Jacques Le Marois over 1600 metres at Deauville. The race resulted in a "blanket finish" in which Lycius produced another fast finish but was beaten a nose by Hector Protector, just ahead of Danseuse du Soir, Polar Falcon and Priolo.^[9]

In the Prix du Moulin at Longchamp Racecourse in September Lycius turned into the straight in ninth place before making good progress and finishing third behind Priolo and Mukaddamah. Danseuse du Soir and Hector Protector finished fifth and seventh respectively. On his final appearance Lycius started odds-on favourite for the Prix de La Foret over 1400 metres at Longchamp on 2 October but never looked likely to win and finished fifth of the seven runners behind Danseuse du Soir.