On a blustery day that must have reminded her of her native Scotland, Matthew shot a 4-under 68 on Thursday for a share of the lead with Young Jo in the suspended first round of the Safeway International on Thursday.
'You don't know what to expect coming out here, since I haven't played for a while,' Matthew said.
Lorena Ochoa and Mi Hyun Kim were a stroke back and Beth Bader and Gloria Park were two strokes off the lead.
Seventy-two players were still on the course when play was suspended because of darkness at 6:06 p.m. Rain and lightning delayed play for about two hours on the Superstition Mountain Golf and Country Club's Prospector Course.
The first round was scheduled to resume at 6:50 a.m. Friday, with more rain in the forecast.
'It was difficult to try to pick the club,' said defending champion Juli Inkster, who shot 1 under. 'The course played a lot longer today, and I thought it played tough out there.'
The weather made scoring a challenge on the 6,620-yard course. Only nine finishers broke par.
'I looked a little bit at the leaderboard and par seemed like it was OK,' said Annika Sorenstam, who was 1 over through 15 holes when play was halted for the day.
Play was first suspended by lightning at 2:31 p.m., the second time weather has played havoc with this tournament in the last two years. Last March, hail forced a two-hour suspension on Sunday, and the final groups played the last two holes under hastily erected spotlights.
Matthew is playing in her first tournament since last August, when she withdrew after one round from the Wendy's Championship for Children in Dublin, Ohio.
Matthew was pregnant with her first child at the time. After giving birth to daughter Katie three months ago, Matthew went back to work on her game in Scotland. Her offseason training paid off immediately.
'After such a long layoff, I've been practicing well,' said Matthew, who has two tour victories, the last coming in 2004.
Matthew birdied the par-4 first hole, hitting a 7-iron from 164 yards to 10 feet and making the putt.
That was the first of Matthew's six birdies. She also had two bogeys, one with a three-putt on the par-5 13th hole.
'I went out there and got off to a good start,' Matthew said.
Jo bogeyed the first hole but bounced back with four birdies in the next five holes. She would have had sole possession of the lead but for a double bogey on the par-5 seventh hole, where she three-putted.
'Except on 7, everything was good today,' Jo said.
Jo, a 23-year-old South Korean, has never finished higher than sixth in 54 tournaments. During the offseason, she hired a new teacher, former tour player Brian Mogg.
'I just fixed my swing,' Jo said. 'My short game wasn't good last year.'
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