Kirk hit a two-run double in the first inning, doubled and scored in the fourth, singled and scored in the sixth and hit a sacrifice fly in the seventh.
Bassitt (13-7) allowed three hits in eight innings.
Jackson finished Toronto’s 13th shutout as the Blue Jays ensured they would not losefurther ground in the AL wild card race. Toronto began the day 3 1/2 games out of a playoff position.
Washington had just two singles and a walk through the first four innings. Rookie Jacob Young hit a two-out double in the fifth but Bassitt promptly picked him off.
Nationals left-hander Patrick Corbin (9-12) lost for the first time in three starts, allowing six runs and 10 hits in six innings.
Kirk hit a two-out, two-run double off the left-field wall in the first. He doubled starting the fourth, advanced on Clement’s single and scored on Espinal's hit. Cavan Biggio followed with a sacrifice fly.
Toronto was 14-13 in August.
Blue Jays: LHP Hyun Jin Ryu (3-1, 2.25 ERA) is expected to start Friday as the Blue Jays begin a three-game series at Colorado.
AP MLB: https://apnews.com/hub/mlb
Ian Harrison, The Associated Press