Port, who won this title in 1995, 1996 and 2000, took eight of the first nine holes Monday en route to her thrashing of Moore
'I feel like I'm a better player now than when I won my other three,' said Port, who was one of three medalists after the stroke-play portion of the event. 'I've worked hard to improve my putting and sand game.
'Today I made a couple of birdies and then she gave me three or four holes. Before you know it, you're buried and you can't get out. I've had it happen to me,' said Port.
Defending champion Laura Shanahan-Rowe also won handily on Monday. She won six of her first seven holes in dispatching Sandy Jacoy, 6 and 5.
Co-medalists Taffy Brower and Lara Tennant advanced Monday as did last year's runner-up, Mina Hardin. Brower, who at 57 is the oldest remaining player, beat Cathy Sigvertsen, 2 and 1, while Tennant, who was the women's golf coach at the University of Oregon in 1994 and 1995, bounced Sharon Hadley, 3 and 1.
Hardin built a 3-up lead and hung on to eliminate Shannon Ogg, 1-up.
Six-time USGA champion Carol Semple Thompson lost to Pat Milton, 2 and 1, on Monday.
Play continues Tuesday with the second and third rounds of match play and the quarterfinal and semifinal rounds are on tap for Wednesday. The 18-hole final match is slated for Thursday.
The U.S. Womens Mid-Amateur Championship is open to all players 25 years or older who have a USGA Handicap Index not exceeding 9.4.