Lyle, 14, from Dunbar, marked her debut in Great Britain and Northern Ireland colours by claiming gold in the T35 100 metres at the European Championships in Swansea.
Coached by Henry Gray, Lyle, who has cerebral palsy, won in a time of 14.92 and said: "I'm really pleased - I've been working really hard towards this and I'm just really glad it's all paid off.
"I try to block out any pressure and just think about what I need to do. The crowd were really amazing. They got behind me, which made me feel confident and raring to go.
"It's important for my parents too because we've been working towards this for a while. It's a big team effort just making my dinner, taking me to training and emotional support so they have been really good.
"It's also been great to be part of the British team - they [her fellow athletes and support staff] have all been amazing."
Lyle's victory came as a timely development for team morale after the news that another star of Glasgow 2014, Libby Clegg had withdrawn from the championships.
The partially-sighted sprinter had been suffering from a viral infection and did not feel fit enough to defend her European title.
There were also gold medals yesterday for London Paralympic champion Mickey Bushell (T53 100m) and Erin McBride (T13 100m), and silver medals for Paul Blake (T36 400m), Isaac Towers (T34 800m) and the T38 100m world champion, Sophie Hahn.
To the delight of the Welsh crowd, Kyron Duke won the final medal of the day for GB & NI as he collected silver in the F41 javelin to take the team's overall tally to six gold, seven silver and 11 bronze medals.
With three days of the competition still to go, the home team with 26 medals trail only Russia (38, including 16 golds) in the medal table.