WASHINGTON — The Nationals knew the Phillies could hit for power when they got hot. But Washington had held its divisional opponents to three home runs across the first two games of the weekend series, and none were allowed by the bullpen. The series finale on Sunday had a different outcome. The Nationals allowed a season-high five home runs in an 11-3 loss to the Phillies at Nationals Park. Right-handers Trevor Williams and Andrés Machado surrendered a pair of homers while Thaddeus Ward gave up one. “I think they have a very good lineup with guys that are built to…