Now, everything gets real crazy.
"We know what's at stake. Obviously we needed to win today, by all means," Rizzo said, "and tomorrow is the same thing."
Shortly after Milwaukee completed an 11-0 victory over Detroit, Jorge De La Rosa worked a hitless ninth inning to move the Cubs back into a tie with the Brewers at 95-67. Yairo Munoz walked with two out, but Pena's harmless fly to right closed it out.
Next up, game No. 163.
Chicago hosts Milwaukee on Monday afternoon and the Colorado Rockies visit the Los Angeles Dodgers as baseball holds a pair of tiebreaker games on the same day for the first time. At stake is the postseason road for each club.
The winner at Wrigley gets a spot in the division series and home-field advantage throughout the NL playoffs. The loser plays again Tuesday night, hosting the runner-up in the NL West in the wild-card game.
"It's interesting that baseball is such a perfect game in some ways that it takes 162 to not decide anything," Cubs manager Joe Maddon said.
St. Louis (88-74) was in contention heading into the final week of the season, but it was swept by Milwaukee before dropping two of three against Chicago. Catcher Yadier Molina, outfielder Marcell Ozuna and infielders Kolten Wong and Jedd Gyorko were held out of the finale due to nagging injuries.
St. Louis missed out on the playoffs for a third straight year for the first time since it went 75-86 in 1999. It finished with a 41-28 record under Mike Shildt, who took over as manager after Mike Matheny was fired on July 14.
"Three straight years of coming up short," said first baseman Matt Carpenter, who finished with a career-high 36 homers. "We as an organization, as a total group, top to bottom, everybody in this clubhouse, all the staff, we have to find a way to get better, to compete if we want to play in October."
The only other time Chicago began the final day of the regular season tied for the lead in its division or league was in 1908, when it beat Christy Mathewson and the New York Giants 4-2 at the Polo Grounds for the NL pennant. The Cubs then won their second straight World Series title before enduring a championship drought that cruised past a century before they won it all again in 2016.
Rizzo and company are looking for another October run, but they have been plagued by an inconsistent offense. It looked like more of the same when Jack Flaherty (8-9) cruised into the third inning with a 2-0 lead and then retired the first two batters.
Then everything changed.
The next six batters reached for Chicago, producing four runs. Rizzo hit a tiebreaking double to give him 100 RBI on the year, waving his arms in the air as he coasted into second. Jason Heyward added an RBI single.
"Just the overall approach today, two outs, a lot of two-out rallies ... just kept things going and kept the line moving," Rizzo said, "and we usually have good success when we do that."
The Cubs broke it open with four more in the fifth. Kris Bryant roped a two-run double into the left-field corner. Two batters later, Willson Contreras hit a drive to left for his first homer since Aug. 1.
"We just couldn't stop them," Shildt said.
Rizzo became the first lefty batter in franchise history with four seasons with at least 100 RBI.
Cardinals: Wisdom was visited by a trainer and Shildt after he was hit by a pitch in the third. The trainer examined Wisdom's left wrist for a short time, but he stayed in the game. ... Wong (left knee) is expected to undergo an MRI in the near future, general manager Michael Girsch said.
Jose Quintana (13-11, 4.09 ERA) will start the tiebreaker for Chicago. Quintana is 6-2 with a 1.60 ERA in 10 career starts against Milwaukee. The Brewers did not announce a starter.
Jay Cohen can be reached at http://www.twitter.com/jcohenap
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