Previous racecourse experience proved crucial as the twice-raced Higher Leaves kept on strongly to deny the odds-on debutant Mother Nature in the Irishinjuredjockeys.com Fillies Maiden at Dundalk.
Fourth on her racecourse debut at Cork in September, the Henry De Bromhead trained Higher Leaves finished third of 12 at Leopardstown on her only subsequent juvenile start.
With the Aidan O'Brien trained newcomer Mother Nature leading from an early stage, Billy Lee was content to track the pace on the eventual winner. Moving closer leaving the back straight, the 11/4 second favourite had the short priced 8-13f Mother Nature off the bridle over 3f out.
To her credit, the latter filly responded to Ryan Moore, staying on in there with every chance all the way up the straight. Higher Leaves drifted right inside the final furlong but there was no real contact as the pair flashed by the winning post in unison.
The judge was needed to split the two fillies with Higher Leaves subsequently getting the verdict by a short head.
Billy Lee said: "She is a nice filly and she had two lovely runs last year. She is learning on the job.
"She will probably get a mile and a-half. She goes on any type of ground, she ran on real soft ground at the backend of last year and she has handled the all-weather well there. She is versatile that way.
"Hopefully, she is a nice filly to go forward with.
"That's it (bit green) - I probably kicked a bit soon and then she has idled a little bit. When the second horse has come to me, she has battled again."