The Wizards (11-10-9) finished the season with a furious kick -- five wins and a draw in their final seven games -- to reach the playoffs. They will be at home Nov. 1 against Columbus to start the conference semifinals.
Lopez scored on a penalty kick in the first half following the ejection of the Revolution's Gabriel Badilla and Khano Smith. Arnaud scored the decisive goal in the second half and the Wizards' third score came on an own goal in the 88th minute.
Jeff Larentowicz scored in the 90th minute for New England (12-11-7), which has clinched third place in the East. The Revs will be at home vs. the Chicago Fire Oct. 30 for Game 1 of their Eastern Conference semifinal series.