Down 4-3 with two outs and no one on base in the ninth inning, Chicago rallied for four runs to take the lead.
It was the Cubs' 103rd win of the year. They were the only team in Major League Baseball to reach the 100-win plateau this season.
"The boxes have been checked in the regular season," manager Joe Maddon said before Sunday's game. "We won the division, we stayed relatively healthy, we've played well. ... All this stuff we talked about in camp regarding embracing the target and dealing with the pressure, we've done all those things."
In the process the Cubs will have multiple candidates for multiple awards. Starting pitcher Kyle Hendricks may have hurt his Cy Young cause a little Sunday as he gave up six hits and four runs over five innings, raising his ERA to 2.13. It's still good enough to win the ERA title by a wide margin. Left-hander Jon Lester finished second in ERA at 2.44, making them the first teammates to finish 1-2 in the stat since the 2005 Houston Astros' Roger Clemens and Andy Pettitte.
With Cy Young candidate Max Scherzer of the Washington Nationals seeing his ERA rise to 2.96 on Sunday, one of the two Cubs could take home the top pitching honor.
"I don't know which one deserves the Cy Young Award," catcher Miguel Montero said recently. "Maybe they can split the award."
At the plate, it's a similar situation between sluggers Anthony Rizzo and Kris Bryant. They combined for 71 home runs and 211 RBIs while each hitting .292. Bryant's 7.6 WAR led all National League players while Rizzo ranked fifth at 5.8 going into Sunday's finale.
Bryant is considered the front-runner for MVP after being named minor league player of the year and rookie of the year over the past two seasons.
There were other major team accomplishments, including the pitching staff leading the league in ERA, while the Cubs' top four hitters all produced on-base averages above .380. But as Lester noted Saturday, the past 162 games will have much less meaning if the Cubs don't go far in the postseason. Their last championship came in 1908.
"This season isn't anything unless we do what we showed up at spring training to do -- win a World Series," Lester said.
The Cubs will have four days off to prepare for their second consecutive postseason appearance. Last year, they were the fun underdog and upset two teams that finished ahead of them in the standings. This year, they enter the playoffs as the team to beat, a near wire-to-wire winner in the division, sporting the best record in baseball for much of the season.
"It's go time," Lester said. "Now we have to live up to the expectations and hype."