The Wizards shot just 32 percent from the floor and managed only 28 points in the second half to have a two-game winning streak come to an end. Toronto had lost two in a row.
DeRozan scored 25 points. Valanciunaus had 10 rebounds to go with his 24 points. Kyle Lowry handed out 13 assists for the Raptors.
John Wall produced 20 points for the Wizards, who melted away in the second half after owning an 11-point lead at the break.