At 10-under-par 134, Nagl is two better than Japans Mayumi Nakajima (68) and Candie Kung (67) of Taiwan.
Despite bogeying her 17th hole of the day (the par-4 8th), Nagl ended her round in fine fashion, sinking a 15-footer for birdie at the 394-yard par-4 9th for 68.
Of her plans for the weekend, the No. 10-ranked player on the Futures Tour Money List hopes to keep it simple.
'Im not going out there tomorrow to do anything differently than I have done the last two days,' Nagl said.
I am very happy with my score and especially with my routine on the course, she went on to comment. I just want to remain focused and take one hole at a time.'
One other player who is in the mix entering the weekend is the tours leading money winner Beth Bauer.
Bauer fired a second consecutive 69 on Friday to move to 6-under 138, and sits just four shots off the pace with three others.
Seventy-one players survived the cut on Friday, which came at 4-over 148. They will each be striving over the weekend for the total purse of $75,000, $10,500 of which will go to the eventual champion.
Click Here for First Round Wrap from the SBC Futures Tour Championship
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