The U.S. Open Cup is renowned for its win-or-go-home drama, and upsets by lower-league teams that rival any from England, France and other soccer powers.
"I'm very happy with the professionalism of the group," Union manager Jim Curtin said. "It's been a wild week. … There was good soccer played tonight. I'm happy with the guys and the intensity that they played with."
Jack Elliot opened the scoring in just the fourth minute, getting on the end of a Haris Medunjanin corner kick.
David Accam doubled the lead with a penalty kick in the 28th minute, after Richmond goalkeeper Trevor Spangenberg took out a hard-charging Cory Burke. It was Accam's first goal for the Union, after 13 games without a goal or assist in his time here.
"I wanted to score my first goal for the club, and today I had the chance," Accam said.
Asked if there was any question of whether he'd take the penalty, he said: "I don't think so." That included some encouragement from Burke.
Anthony Fontana made it 3-0 in the 43rd with his second goal of the year, pouncing on a Richmond turnover and shooting from close range. Epps made it 4-0 in first half stoppage time with a slashing run down the right wing, including a crossover dribble that left a Richmond defender on his rear end.
Jay Simpson joined the party as a halftime substitute, and added his name to the scoresheet just three minutes after taking the field. Derrick Jones had the assist. It was Simpson's first goal for the Union since March 11 of last year.
In addition to lifting the Union's spirits, the scoring outburst backed up Curtin's lineup rotations for the night.
Fontana played for the senior team for the first time since May 9, and started for the first time since March 3. Matthew Real did so for the first time since April 13, and Derrick Jones did so for the first time since March 3. John McCarthy gave Andre Blake the night off in goal, and was rarely troubled.
Auston Trusty also got a few minutes on the field as a late substitute, making this the first game in which all five current Union homegrown players played. Curtin said they would have all played together had Fontana not picked up a cramp.
"We weren't nervous in giving these guys an opportunity," Curtin said. "Whether you agree with it, whether you don't agree with it, we are committed to it, and I think that was clear tonight."