The Nationals won the opener 2-0.
Scherzer (6-4) had won each of his previous five starts. That streak ended as he allowed four runs on six hits over six innings.
Pillar hit a solo shot in the second and, after Washington scored two in the fourth and one in the fifth, he put Toronto back in the lead with a three-run homer down the left-field line. The centre fielder also singled against Scherzer.
Marco Estrada (2-3) pitched six innings, allowing three runs — two earned — and six hits.
Tyler Moore drove in two runs for the Nationals.