Although there were cheers from the bars around Wrigley Field as soon as the Giants-Cardinals game ended, the Cubs' party will come after Friday's game, scheduled for a 1:20 p.m. CT start time.
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"We want to come back here [Friday] and we'll be together and celebrate the way you're supposed to after a win," Cubs catcher Miguel Montero said.
"Last year was exactly the same," Montero said. "Regardless, we have to come back [Friday] and win the ballgame. We've been playing good enough to not quit now. We want to keep rolling."
The Cubs are the first team to clinch a division title on Sept. 15 or earlier since the 2008 Angels did so on Sept. 10. The last NL team to win a division title by this date was the 2005 Cardinals (Sept. 15).
Chicago reached the postseason last year by virtue of a Wild Card berth, and this year, it wanted to avoid a one-game playoff scenario. The Cubs now have made it to the postseason in consecutive seasons for the fourth time in franchise history. They also did so in 1885 and '86, and again in 1906-08 and 2007-08.
Cubs manager Joe Maddon wasn't going to wait at Wrigley for the outcome of the Giants game, which ended around midnight CT.
"This is just the first step," Maddon said. "We have much larger baseball fish to fry in our skillet. Let's just get this done. I thought our guys were ready to play tonight."
The Cubs were largely silent on social media, clearly focused on the bigger picture: winning in the postseason.
Were the Cubs anxious? The crowd of 41,362 at Wrigley Field was definitely amped, especially after Jorge Soler's two-run homer in the second gave the Cubs a 2-0 lead.
"I'll use the word 'eager,'" Maddon said. "I think that's a good word, better than anxious. They were ready to go."
Jason Heyward, who hit an RBI double in the eighth, planned on his usual postgame routine. He was going to get dinner and then check the scores. If he was still in the Wrigleyville area, all he had to do was listen to the cheering fans and honking car horns.
"We didn't earn it with a win tonight," Heyward said. "[The Brewers] played us one run better. We'd like to think about it as it's not up to anybody else, it's up to us."