McCook who back in May won a three-way play-off to take victory at a Rose Series Ladies Event, had a rollercoaster of a round.
The 29-year-old from Nethy Bridge got off to a strong start rolling in birdies on holes two, five, eight and nine with only one bogey on the fourth.
Yet, at the turn McCook struggled to continue momentum and carded four bogeys on the back nine but brought her game back with a birdie on the 17th.
Speaking about her round, McCook said: “The round wasn’t that steady unfortunately!
“The front nine was very solid and then the back nine was a little bit more stressful but I held it together to finish level.
“I was free flowing in the front nine, and then it was like a switch that went on and I suddenly got more defensive, which is infuriating especially when you are playing well but start to get all tense.
I then tried to relax and keep staying in the moment. It was windy again, like yesterday at times.
McCook believes she will take plenty of encouragement from going into the final day as a leader but wants to keep calm.
“I just want to play as well as I can and try not to think of the outcome.
“I will try and stay in the moment and as cliche as it is, take a shot at a time. I’ve been in the final group before, so I’ll try and use that experience tomorrow.
“It’s just nice to be in this position, and whatever happens happens.”
Joining McCook on three-under-par is Danish amateur Natacha Host Husted, starting on hole ten the 21-year-old got off to a great start with a faultless front nine, carding three birdies.
However she struggled to keep up the momentum and made two bogeys on holes four and six but she made a birdie on the eighth to finish the day off nicely on two-under-par.
“My round today was quite a grind actually,” the Danish National Golfer admitted, “It started off smooth but towards the end it became a little more shaky, but I managed played to my strengths most of the way despite a few bogeys.”
Going into the final tomorrow, Host Husted admits to feeling the nerves but is determined to embrace the challenge of playing in the final group.
“I am excited about tomorrow. Knowing myself I am going to be a little nervous, but since I am only an amateur I will primarily take it as an opportunity to learn from.
“I am happy to have played my way to this position and I plan on continuing with the same game plan tomorrow and then I’ll see where that takes me.
Conditions have not been in our golfers’ favour this week at Uppsala GolfKlubb, as Host Husted explains: “The weather has been a rough challenge to manage. It’s been windy both days and the course is wet, so it plays a lot longer than other courses.
“However, it’s been a fun challenge and I’ve been able to use my strengths especially off the tee well.
“It would be amazing to win it tomorrow and a great way of proving to myself that I can compete with some of the best players.”
Three players sit in third place three shots behind the leaders: two Irish amateurs Sara Byrne and Anna Foster alongside Finland’s Emily Pentilla.
Whilst Sweden’s Corrine Viden, Denmark’s Sofie Kibsgaard Nielsen, Australia’s Kelsey Bennett, and Finland’s Tia Teiniketo all sit in sixth position on one-over-par.
The cut fell at +7 with 63 players making it through to the Thursday in Sweden.
The third and final round will begin at 8:50am local time tomorrow, with the leaders going off at 10:40am.
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