The Flying Squirrels (29-36), the Double-A affiliate of the San Francisco Giants, allowed 12 hits and 10 walks to the Senators (31-33), the Double-A affiliate of the Washington Nationals, in the setback.
Harrisburg jumped ahead, 2-0, in the top of the first inning with an RBI by James Wood and a run-scoring single by Frankie Tostado against Richmond starter Ryan Murphy (Loss, 1-4).
Richmond tied the score, 2-2, in the bottom of the first. Shane Matheny brought in a run with a single. Later in the inning, Marco Luciano scored from third while Matheny was caught in a rundown between first and second base on a steal attempt.
The Senators moved ahead, 3-2, in the top of the second when J.T. Arruda scored on an error by first baseman Carter Aldrete.
The Senators pushed the lead to 10-2 with a seven-run fourth inning. Donovan Casey hit an RBI single, Tostado followed with a two-run double and Trey Lipscomb doubled him in. Leonel Valera brought home a run with a single and Robert Hassell III capped the frame with an RBI groundout.
Lipscomb extended the lead to 11-2 with an RBI single in the seventh.
Brandon Martorano hit a solo home run, his third of the year, in the bottom of the seventh to close the score to 11-3.
Harrisburg starter Jackson Rutledge (Win, 6-1) tied a career high with four walks but allowed two runs over six innings with six strikeouts.
The start of the game was delayed 31 minutes for rain.
The series continues with a doubleheader on Friday night. Game 1 is scheduled to begin at 5:05 p.m. Richmond lefty Carson Whisenhunt (0-0, 4.15) will make his second Double-A start opposed by Harrisburg lefty Dustin Saenz (0-1, 9.82). In Game 2, right-hander Carson Seymour (0-1, 3.26) will be on the mound for the Flying Squirrels and left-hander Alemao Hernandez (1-2, 3.55) will pitch for the Senators.
The Flying Squirrels celebrate their fourth-annual Pride Night with Virginia Pride on Friday night. The first 1,000 fans ages 15 and up will go home with a Pride T-shirt presented by CarMax. It is also Funnville Friday Happy Hour with two-dollar, 12-ounce domestic beers at all concession stands and two-dollar fountain sodas at the Pepsi Fountain.
The ballpark gates open at 4:30 for the single-admission doubleheader.
Tickets are available online at SquirrelsBaseball.com/Tickets, by phone at 804-359-FUNN (3866) or in person at the Flying Squirrels ticket office.