Koch, a Swedish LPGA Tour regular who played on Europes winning Solheim Cup team last year, shot a 68 to match the days second-lowest round. She was at 7-under 209 with Morgan (69), a native of Wales who also plays on the LPGA Tour.
Sorenstam had her best score so far on Ullnas tough lakeside course. The Hall of Famer grew up a short drive away, but she has not played the course since she was an amateur 15 years ago.
Sorenstam has won this event three times when it was known as the Compaq Open.
I played much better today, said Sorenstam, who started birdie-birdie and then just missed a third straight. Im two behind and anything can happen tomorrow. Hopefully, Ill start with two straight birdies again and put some pressure on them.
Koch made her only mistake on the first hole'a bogey.
I hit my irons really close and made some putts, said Koch, whose last European Tour win came in the Chrysler Open four years ago in Sweden.
Morgan has often been in contention on both tours but never won.
Now I have the chance, she said. Ive never won in the states or Europe, but I lost a playoff in France once. I love this course and its going to be really inspiring to play in the last group tomorrow.
Scotlands Janice Moodie, tied for the lead with Morgan at the halfway point, slipped to a 72 and was at 212. Frances Stephanie Arricau (68) was at 213. Swedens Liselotte Neumann had the days best round at 67 and was at 215.
Ullna is considered one of Swedens best courses and hosted five mens European Tour events in the 1980s. Tiger Woods played the SAS Invitational Match Play event at Ullna four years ago and lost to Swedens Jesper Parnevik.
The worlds top women havent played there since 1982, when Nancy Lopez and Sally Little were on a U.S. mixed team that beat Sweden.
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