Joe Maddon thinks the Cubs have caught their second wind.
At this point, it's pretty much impossible to argue that.
The Cubs (64-48) pulled out their sixth straight victory Wednesday night, walking off the Milwaukee Brewers, 3-2, in front of 36,438 fans at Wrigley Field.
After Hector Rondon blew a save by allowing an unearned run in the ninth, Miguel Montero ended it with an opposite-field blast to lead off the 10th inning.
Montero and the Cubs were on Cloud Nine in the clubhouse after the game.
"Right now, the feeling in the clubhouse is we're pretty unbeatable," Montero said. "... That's the kind of feeling that we actually get and hopefully it stays there and we keep believing it.
"We got a good ballclub. The young guys are just getting better and better. There's no reason why we should not win."
Before Tuesday night's game, Maddon spoke about how well the Cubs rookies have been playing, and they delivered again Wednesday as Kris Bryant homered and Addison Russell drove in a run with a two-out hit in the fifth inning.
Maddon said the Cubs were like a car that wouldn't quite turn over ("Like my old '65 Plymouth that Uncle Chuck used to drive all the time") coming out of the All-Star break.
"And then, eventually, it turns over, and all of a sudden, guys start feeling it a little bit," Maddon said. "I thought there was a certain amount of mental fatigue post-break. I think we're getting through that somewhat right now.
"And like I said, you put yourself in position, now it's the playoff hunt in September, energy just shows up. You don't have to look for it; it's there.
"So we're looking for that component that takes care of that, so that when you arrive at that moment, you're ready to rock and roll. That's what our guys are starting to get."
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The Cubs had only four hits Wednesday, but they made them count and played some stellar defense behind starter Jason Hammel and four relievers.
"There you go, man: Pitching and defense getting it done again," Maddon said. "I could not be more proud of our guys. ... If we don't play that kind of defense, we do not win it."
Anthony Rizzo made the highlight-reel play, jumping completely into the stands to make a catch in the sixth inning to ignite the crowd and the dugout ("Even old man David Ross was fired up," Rizzo said).
"These games are really helping us get into that strong mentality of, 'we can do this,'" Anthony Rizzo said. "Not that we haven't had that all year, but all year we've been grinding - five or six games over .500. Up to eight or nine [over], then go back down.
"We never really got into a nice little run. Right now, we feel that and everybody feels really good about it."
It was the Cubs' 12th win in their last 13 games. The Cubs gained a game on their direct competition Wednesday, pulling to within 1.5 games of the Pittsburgh Pirates for the first wild card spot and extending their lead to 4.5 games over the San Francisco Giants for the second wild card.
"I couldn't be more proud of this group," Maddon said. "Most of them are young, but they come to play. I think they've gone through that intimidation moment or that 'happy to be here moment.'
"I think they feel like they belong here right now and they're showing up with a good look."