CHICAGO -- Cubs spark plug Nicholas Castellanos lifted his bat overhead with both hands and slammed it to the dirt in celebration. It was only the second inning, and already the Brewers were well on their way to a loss that hurt in more ways than what it means in the standings.

Castellanos smashed two-run homers in each of the first two innings as Chicago built a five-run lead before Chase Anderson recorded his sixth out of the Brewers’ 7-1 loss at Wrigley Field, a defeat that was doubly costly because Milwaukee lost second baseman Keston Hiura in the fifth inning with a hamstring injury.

• Hamstring discomfort ends Hiura's day early

“We have to figure out what we need to do now and get on a run,” Anderson said. “September’s coming on Sunday. For this team to play an October game, we’re going to have to get after it, that’s for sure.”

• Box score

The math is getting tough for the Brewers with 28 games to go. Their fourth loss in five games dropped them six games behind the first-place Cardinals in the National League Central. The Cardinals were scheduled to begin a three-game series at home against the Reds on Friday night, but the game was postponed due to rain and will be made up as part of a doubleheader on Sunday,

And unlike last year, when the Brewers overcame that kind of deficit to win the division with the Wild Card in their back pocket, those standings are just as daunting this year. Friday’s loss dropped the Brewers five games behind the Cubs for the NL’s second Wild Card berth.

“Unfortunately, [Anderson] made some poor pitches early in the game,” manager Craig Counsell said, “and they were ready to go.”

So was old foe Jose Quintana, who delivered an RBI double for the Cubs while pitching another gem at the Brewers’ expense in the first of seven games in the span of 10 days behind these division rivals. With 5 2/3 scoreless innings on Friday, Quintana improved to 8-4 with a 2.65 ERA in 16 career starts against Milwaukee.

The Brewers have hit him at times this season, and had a chance to do so again on Friday when Christian Yelich doubled before walks to Ryan Braun and Yasmani Grandal loaded the bases with one out for catcher Manny Piña, who started the day with a .997 OPS against left-handed pitchers. Pina had doubled off Quintana in his first at-bat.

This time, Pina was rung up by plate umpire Mike Muchlinski on a curveball down and away. When Hernan Perez struck out swinging, Quintana was out of trouble.

“We had a good inning working there, and we have to capitalize on that inning, and we didn’t,” Counsell said. “To me, that was the inning. Bases loaded with Manny there. We had [Quintana] on the ropes. … That inning was our inning to put the game back within reach.”

The left-hander had an early lead thanks to Castellanos, who hit a two-run home run off Anderson in the first inning and another two-run home run with two outs in the second. Castellanos has 11 home runs in his first 27 games since a trade to the Cubs, matching his power output in his first 100 games this season for the Tigers.

“The last time I faced him was in the Fall League in 2012, and he's been a player ever since,” Anderson said. “You tip your cap to him. They traded for him, and he's done really well since coming over here. I know he was going into free agency and he wasn't playing like he wanted to in Detroit. He gets traded over here, kind of new life, and he's carried their team a little bit." 

And he's done it with some flair. When Castellanos turned on an inside changeup and sent it to the left-field bleachers in the first inning, he pumped his fist after rounding first base.

An inning later, he went further, lifting his bat over his head and throwing it down. 

“I don’t really have an explanation. I didn’t mean to do that,” Castellanos said. “It just came out. It’s just how I felt like expressing myself in that moment.”

Asked if he took note of Castellanos’ reaction, Counsell simply said, “No.” 

And Anderson? 

"Honestly, I didn't see it,” Anderson said. “I was focused on, 'He hit another homer.' I obviously wasn't looking at him. Hitters are going to do what they're going to do. You make better pitches and you get them out, they don't do that stuff.” 

Anderson entered the day having allowed three runs or fewer in 11 of his last 12 starts, including two or fewer in 10 of those games. But now two of his last three starts have been duds; he gave up 10 earned runs on nine hits in 2 1/3 innings at Washington on Aug. 18, and five earned runs on seven hits in four innings on Friday. 

“The other starts have been really, really good, and you understand that sometimes we’re going to give up some runs through the course of a game,” Counsell said. “But when you get behind the eight-ball early like this, it’s challenging, for sure.”