Anthony Rizzo hit a grand slam, Willson Contreras homered twice, and the Chicago Cubs overcame an early four-run deficit for a 17-8 victory over the Pittsburgh Pirates on Friday afternoon.

The Cubs (79-68) beat the Pirates (65-83) for the eighth time in the past nine home meetings. Chicago is one game ahead of the Milwaukee Brewers for the second National League wild-card spot.

Nicholas Castellanos and rookie Nico Hoerner hit two-run homers as Chicago capitalized on friendly wind conditions and produced its highest run total of the season. The wind was blowing out to center field at 20 mph at first pitch.

Hoerner also had a two-run single, pinch hitter Jason Heyward added a bases-clearing double, pinch hitter Tony Kemp had an RBI single and Castellanos added an RBI double in Chicago's seven-run fifth.

Jon Lester (13-10) allowed seven runs (four earned) and 11 hits in five innings. He walked two and struck out two. After Brad Wieck pitched a scoreless sixth, Alec Mills allowed a run over the final three innings and was awarded his first career save.

Pablo Reyes hit a two-run triple and Adam Frazier had an RBI double for the Pirates.

Pittsburgh's Steven Brault (4-5) was tagged for 10 runs on eight hits in 2 2/3 innings. He walked three and fanned two.

The first inning lasted 42 minutes as the teams combined for nine runs.

The Pirates' Kevin Newman scored on throwing errors by catcher Contreras and center fielder Albert Almora Jr. on a walk to Bryan Reynolds. Pittsburgh added two runs on Reyes' triple to the warning track in right-center, and Reyes scored on Frazier's double for a 4-0 lead.

Castellanos hit his 15th homer as a Cub and 26th of the year by sending a pitch to left field to cut the deficit to 4-2. Contreras made it a one-run game by homering to center, and after a Kyle Schwarber double, Hoerner blasted the first pitch he saw at Wrigley Field to center field for a 5-4 lead.

Chicago added five more in the third. Contreras blasted his second homer to center field to start the inning. After a walk and a single, Brault walked Lester to load the bases, and Rizzo followed with his fifth career grand slam to knock out the Pittsburgh starter.

Pittsburgh first baseman Josh Bell exited the game after the top of the fifth inning with an undisclosed injury.

--Field Level Media