Mehaffey, who won the Irish Strokeplay Championship a fortnight ago, carded a five under par 67 on the Portland course. Her nearest rival is Sweden’s Linda Lundqvist with four players tied for third on two under par, including Ulster duo Paula Grant (Lisburn GC) and Jessica Ross (QUB).
“I’m just coming back from illness and I won last week so it is nice to have a wee bit of momentum,” said Olivia who is still shaking off the effects of a bout of glandular fever.
“The conditions are so much better this year and I felt I needed to make the most of it this morning because I don’t know what we’ll get in the next two days.
“It’s nice to be back here as this is definitely one of my favourite courses and I played well.
“I got off to a good start birdieing the first so it is a nice solid start. I had a good front nine but it was a wee bit frustrating on the back nine as I missed a few putts.
“They were good putts just bad lines, and it was nice to finish with a birdie on the last.”
This year’s Helen Holm Trophy has added importance as it is the final competition before the GB&I team is selected for the Curtis Cup. Captain Elaine Farquharson-Black from Aberdeen, who won the Helen Holm in 1987, will name her team next week for the biennial contest against the USA which takes place at Dun Laoghaire Golf Club in June.
Olivia and world number one amateur, Leona Maguire (Slieve Russell), are likely to be key members of the team.