CHICAGO — Willson Contreras led off with a double and became a rare leadoff hitter with a first-inning grand slam as the Chicago Cubs burst to an eight-run lead and beat the Pittsburgh Pirates 9-0 on Monday night.

Contreras became the 10th leadoff hitter since 1901 with a first-inning slam, the first since Houston’s George Springer off Kansas City’s Edinson Vólquez on June 24, 2016. The slam was the 100th homer of Contreras’ career, making him the third Cubs catcher to reach that mark along with Gabby Hartnett and Jody Davis. Contreras became the first Cub with two extra-base hits in an inning since Javier Báez on May 1, 2019.

Wade Miley (1-0) retired his first 14 batters before Michael Chavis lined a single to left and ended a 13-inning hitless streak for Pittsburgh batters. The Pirates didn’t get any hits in a 1-0 win over visiting Cincinnati on Sunday and had not gotten a hit since Rodolfo Castro’s seventh-inning single during Saturday’s 3-1 win.

Miley started the season on the injured list with elbow inflammation and made his second start with Chicago after he was claimed on waivers from the Reds in November. He allowed just the one runner in seven innings and struck out six, throwing 83 pitches.

Miley’s previous win was on Sept. 7, 2021 at Wrigley Field when he beat the Cubs as a member of the Reds.

Michael Rucker finished with two-hit relief, and the Cubs won their third straight.

Pittsburgh is batting .223 this season.

Ian Happ had three hits, including a double in the first, and scored three runs as Chicago ended a six-game slide at home and improved to 5-11 at Wrigley Field. Yan Gomes also had three hits, including a double.

Contreras led off with a double off Dylan Peters (3-2) and scored Chicago’s first run, then lined his fourth slam to left- center off Bryse Wilson on the first pitch of his second at-bat. Happ also had two hits in the first as the Cubs chased Peters, who faced seven hitters and retired only two. All five Cubs who reached against Peters scored.

Wilson was charged with the next three Chicago runs.

The Cubs added an unearned run in the fourth when Happ scored from third on Gomes double-play grounder.