The Royal County Down Ladies and Arizona State University star shot a one-over first round 73 at Lausanne yesterday, as Zhen Bontan of the Netherlands headed the field after her four-under 68.
World number 10 Mehaffey began well with a birdie at the first and, after back-to-back bogeys on four and five, reached the turn in 36 after holing another birdie on the seventh.
She stuttered with bogeys on 10 and 13, but finished well with a birdie on 17 and will be hoping for a strong round today to put her back in contention.
The 19-year-old Curtis Cup player finished third at this event last year.
Elsewhere among the Irish contingent, Jessica Ross from Clandeboye isn’t out of it despite carding a two-over 74 yesterday, but it was a struggle for Forrest Little’s Julie McCarthy and Chloe Ryan (Castletroy) who signed for rounds of 77 and 79, respectively.
The 144-strong field will be cut at 60 and ties after 54 holes.
Meanwhile, Vagliano Trophy player Annabel Wilson (Lurgan) and Sara Byrne (Douglas) will bid to make their mark in the girls’ event at the European Young Masters in Oslo, Norway, which begins this morning.
The 54-hole three-day stroke play tournament features the best under-16 golfers from across Europe, with Aaron Marshall (Lisburn) and Luke O’Neill (Connemara) going for glory in the boys’ championship.
Alongside the individual boys’ and girls’ events, the best three cards of all four Irish players for each round will also count towards the overall score in the team event. Lisa Maguire won the girls’ individual title at Chantilly, France, in 2008.