The 62-year-old Ryan, from Taylorsville, Illinois, beat Michael Dunsmore of Poughkeepsie, New York, 5 and 3 in the quarterfinals and topped Tim Jackson of Germantown, Tennessee, 1 up in the semifinals.
"I don't know what to say. I'm at a loss for words," Ryan said. "To be honest with you, I'm a little shocked. I was fortunate to beat him [Jackson] and Paul Simson [in the round of 16]. Those are two tough guys to take down."
The 57-year-old Sughrue, from Arlington, Virginia, edged Doug Hanzel of Savannah, Georgia, 1 up in the quarterfinals and rallied to beat Kevin Cahill of Waukesha, Wisconsin, in 19 holes in the semifinals.
Against Jackson, Ryan won the 14th hole to take a 2-up lead, lost the 15th with a bogey and matched Jackson with a par-birdie-par finish -- holing a 9-footer on 18 -- to close out the match.
"It was uphill and I just had to hit it," Ryan said. "Fortunately, it went in. That's a tough hole."
On Tuesday in the round of 16 against two-time champion Simson, Ryan had the third known hole-in-one on a par 4 in USGA history.
Against Cahill, Sughrue lost the 15th and 16th holes to fall 1 down, won the 18th with a par and won the match on the 19th with another par. Sughrue also rallied against Hanzel, winning 15 and 16 to take the lead and matching Hanzel with pars on the last two holes.
"The Hanzel match was a real grinder. It was a tough match against a great player," Sughrue said. "We didn't play as well in this one, but on the back nine, we both kind of steadied -- and coming down the stretch, it's not stroke play, it's a matter of who wins the match."
Sughrue left the insurance business after 25 years in 2008 to go to graduate school at Virginia Tech, and he is now a psychotherapist.