The 50-year-old Riegger, making his fifth career start on the 50-and-over tour, had an eagle for the second straight day and added seven birdies and a bogey to finish at 11 under at TPC Snoqualmie Ridge.
Riegger pitched in for the eagle on the 590-yard, par-5 15th hole.
''It wasn't anything fancy'' Riegger said. ''It was just a straight-forward pitch. It landed just on the green and rolled in just like putt.''
He said he no idea at the time that shot pushed him into the lead
''I don't look at it (scoreboard),'' Riegger said. ''If I just go out there and play the way I'm capable of playing, things will take care of themselves. It's not going to do any good to worry about what someone else is doing.''
Riegger won twice on the Web.com Tour, the last in 2010.
''That tour helped me prepare for out here than the regular tour just because you have to go low and keeping going low because there's so many good players,'' Riegger said. ''As for my fifth event, these guys have been beating up on me for 30 years. We still have one more day to go and there's a lot of great players out here. There's some guys out here capable of shooting 63 or 64 on this golf course.''
Langer, the 2010 winner, chipped in for eagle in the 529-yard, par-5 eighth.
''Those were three beautiful shots for the eagle,'' Langer said. ''Then I hit it into the water next hole (for bogey). ... It's not over. Three shots sound like a great deal. On this golf course, it can be gone in a hole or two. There is a lot of golf to be played yet. I think whoever is within five shots has a chance. I've won tournaments when I was seven shots back.''
Lehman birdied his final three holes.
Hometown favorite Fred Couples was 5 under after a 70.
Scott Hoch withdrew because of an ankle injury.