James Shields and Justin Verlander hooked into a pretty good pitchers' duel. With Verlander exiting after seven innings with an injured thumb and a 3-2 lead, the Royals tied it in the eighth and eventually won it in the top of the 10th.
After a bases-loaded walk to George Kottaras produced the go-ahead run, Alex Gordon left no doubt with a grand slam, 443-foot bomb to center which iced the game.
Gordon had earlier singled and was stranded, leaving him at 2-for-6 for the game, slightly reducing his .337 batting average. His homer was the second of the season for the leadoff left fielder. He has driven in 15 runs.
The result left matters in an unsettled tie for the brief, two-game series after the opening game Tuesday was rained out. The Tigers won, 7-5, on Wednesday.
The Nationals find themselves four games back in the division, tied for second place with the Mets.
Washington got all over Reds' starter, Brandon Arroyo, building a 6-0 lead before Joey Votto's solo home run in the fourth got Cincinnati on the board.
Votto's fourth homer was the only mistake Gio Gonzalez made, allowing just the one hit and two walks while fanning seven over eight sparkling innings on the mound, improving to 2-1.
Danny Espinosa provided the offensive spark for the Nats, doubling in the first run of the game and later in the second inning scoring to open a 2-0 lead. In the fourth, Desmond added to what was already a 4-0 lead with a two-run homer, his second of the season.
Bryce Harper socked his eighth of the season to start the third and Denard Span had three hits and drove in three runs.