Willson Contreras homered and drove in three runs, Alex Avila homered for his first hit with the Cubs and Chicago beat the Washington Nationals 7-4 on Saturday to even the series between division leaders.
Kris Bryant and Jon Jay each added a run-scoring hit as the Cubs snapped a three-game losing streak.
Bryce Harper hit his 28th homer and threw out a runner at third base for the Nationals.
Saturday was supposed to be a day off for Contreras — with Avila making his first start after being acquired on Monday — but manager Joe Maddon started Contreras in left field to keep his hot bat in the lineup. He entered batting .429 with two homers and eight RBIs in the first four games of the home stand.
John Lackey (9-9) allowed three runs (two earned) and six hits in five innings to win his fourth straight start. Wade Davis got the final three outs — striking out Harper, the potential tying run, to end it — for his 23rd save.
Washington starter Edwin Jackson (2-2) allowed four runs and six hits in five innings.
Harper's solo shot in the first gave the Nationals a quick lead, but the Cubs responded with four in the bottom of the inning. Bryant drove in the first run with a double and Contreras followed with an RBI single to score Bryant. After a single by Ben Zobrist — Contreras was thrown out by Harper trying to advance to third — Avila's two-run shot made it 4-1.
Washington scored twice in the fourth to make it 4-3. Anthony Rendon had a sacrifice fly and Matt Wieters added an RBI single.
Contreras' two-run blast off Matt Grace in the sixth was for a 6-3 lead and Jay's RBI single in the seventh made it 7-3.
The Nationals added an unearned run in the eighth to cap the scoring.