[4] On her racecourse debut, Dark Lomond contested a maiden race over six furlongs at the Curragh in October and finished strongly to take second place, three quarters of a length behind the John Oxx-trained Catina.
At the end of the year the independent Timeform organisation gave her a rating of 88 p (the "p" indicating that she was expected to make more than usual improvement) and commented in their annual Racehorses of 1987 that she was "sure to win races".
On her seasonal debut she started the 4/6 favourite for a Listed race over ten furlongs on heavy ground at Phoenix Park Racecourse on 4 May but was beaten into second place by the outsider Viqueen.
After being restrained by Reid in the early stages, she moved into contention in the last quarter mile and then produced a strong late run up the inside rail to win by a length and a neck from Skating and Ardglen.
[7] After a break of over two months Dark Lomond returned in the Meld Stakes at the Curragh on 27 August, and finished second, half a length behind the British-trained filly Sailors Mate, to whom she was conceding five pounds in weight.
Declan Gillespie took over from Reid when Dark Lomond was the only three-year-old filly in the thirteen-runner field which contested the Irish St Leger over fourteen furlongs at the Curragh on 24 September.