CHICAGO -- Kris Bryant had three hits, including his 27th homer, and the Chicago Cubs overcame the ejections of John Lackey and Willson Contreras on their way to an 8-2 victory over the St. Louis Cardinals on Friday.
Bryant went deep in the fourth and singled twice in Chicago's seven-run sixth, helping the NL Central leaders open a big weekend series on a winning note.
The Cubs moved four games ahead of the Cardinals. Milwaukee, which began the day tied with St. Louis, was scheduled to play Miami on Friday night.
Lackey and Contreras were thrown out with Chicago trailing 2-1 in the fifth. But after outscoring the New York Mets 39-14 in a three-game sweep, the Cubs got enough big hits to improve to 9-4 against the Cardinals this year.
Tommy Pham homered for St. Louis. But the Cubs chased Carlos Martinez in the sixth, sending 11 batters to the plate and grabbing an 8-2 lead.
Bryant led off with a single and Chicago poured it on from there.
Alex Avila -- who came in for Contreras -- drove him in with a single. Jon Jay put Chicago ahead 3-2 with a single to center.
Avila scored when Martinez (11-11) bobbled Javier Baez's comebacker and bounced the throw to the plate. Matt Bowman came in and gave up a two-run single to Ian Happ, a sacrifice fly to Ben Zobrist and an RBI single by Bryant that made it 8-2.
Lackey and Contreras were tossed after arguing with plate umpire Jordan Baker in the fifth.
The Cardinals had runners on first and second with two out when Lackey screamed at Baker after he called a ball on a 2-2 pitch to Martinez near the knees and outside corner. Martinez lined the next pitch for an RBI single, giving St. Louis a 2-1 lead, and the 38-year-old Lackey screamed again at the umpire as he ran toward the plate.
Contreras also got into it with Baker and slammed his catcher's mask to the ground. He was restrained by manager Joe Maddon.
Lackey gave up three hits in 4 2/3 innings. Carl Edwards Jr. (4-4) pitched a perfect sixth for the win.
Martinez gave up seven runs and six hits in 5 1/3 innings.
Cardinals: 2B Kolten Wong departed with tightness in his lower back. He was lifted for a pinch hitter in the seventh. … CF Dexter Fowler (bruised knee) remained sidelined. He was hurt when he crashed into the wall trying to make a catch against Pittsburgh on Saturday. … RHP Adam Wainwright (right elbow) is expected to throw a bullpen session Saturday.
Cubs: SS Addison Russell hopes to return this weekend after being sidelined since Aug. 2 because of plantar fasciitis in his right foot. If not, he could be back early next week. Russell is scheduled to work out Saturday. … RHP Jake Arrieta (strained right hamstring) is scheduled to throw a bullpen session.
The Cubs send RHP Kyle Hendricks (6-5, 3.35 ERA) to the mound while the Cardinals go with RHP Michael Wacha (12-7, 3.99 ERA).