MILWAUKEE -- The Chicago Cubs wrapped up the 2015 regular season on a high note Sunday, finishing off a three-game sweep of the Milwaukee Brewers with a 3-1 victory at Miller Park.

Next up for the Cubs is a trip to Pittsburgh for the National League Wild Card Playoff, set for Wednesday night at PNC Park.

"We're going to go there and play and play pretty good about it," Cubs manager Joe Maddon said. "I'm very proud of each and every one of our guys."

Chicago began the day with a chance to host the game, needing a victory and a Pirates loss. The Cubs did their part, getting six strong innings from right-hander Dan Haren, who scattered three hits and a walk and struck out three.

Chicago's offense did not do much against Brewers right-hander Jorge Lopez, who was making his second career start, but took advantage of some early luck.

Lopez hit leadoff batter Austin Jackson with a pitch then walked Chris Coghlan and Kris Bryant to bring up Rizzo who smacked a 1-2 fastball to right and crossed the century mark for RBIs this season.

Lopez finally got outs on the board when second baseman Starlin Castro bounced into a double play. Bryant scored on the play, but Lopez escaped bigger damage when he retired left fielder Chris Denorfia on a groundout to third.

"When you put three hitters on without putting the ball in play, you're going to give up runs there but I thought Jorge pitched well," Brewers manager Craig Counsell said. "I really don't think they squared up against him at all."

The early lead proved to be plenty of cushion for Haren (11-9), who scattered three hits and a walk to earn his third victory in his last five starts.

"Danny Haren finished really strong," Maddon said. "I gave other guys an opportunity out of the bullpen and they were wonderful. We got just enough runs again. Kind of the game we've been playing the week or 10 games."

Lopez (1-1) was making his second major league start. He was named the Brewers Minor League Pitcher of the Year after going 12-5 with a 2.26 ERA at Double-A Biloxi, went five innings and allowed just the three first inning runs on six hits and three walks with three strikeouts.

"I just kept battling and tried to compete," said Lopez, who hoped to at least earn consideration for a spot on the big league roster next season. "I'm going to work hard this offseason and try to make some adjustments and try to be ready and come back next year."

Led by two innings from rookie right-hander Yhonathan Barrios, Milwaukee's bullpen put up zeroes the rest of the way but aside from an RBI double by Shane Peterson in the third, the Brewers' offense could not do much against the Cubs' pitchers and finished the day with just three hits -- and only nine for the entire three-game series.

"We didn't swing the bats well," Counsell said. "Some guys finished slow, for sure, but we've lost a lot of guys out of our lineup and have been putting guys in spots we wouldn't normally."

The Cubs now sets its focus on the Pirates, who they beat in 11 of 19 meetings this season. Maddon said the last couple games have helped make decisions in setting the Cubs' postseason roster, but it was not yet set in stone.

"We're pretty close," Maddon said. "I don't think it will be a difficult decision when we get there because we've done work in advance of the moment."

The players, meanwhile, many of them early in their major league careers, were savoring the moment.

"We did a lot of good things this year," Rizzo said. "Fast forward from a year ago, we put our organization in a great position top to bottom for success. Now it is on us players to go out and repeat that success. Joe said at the beginning of spring training that the hardest thing to do is crack the postseason the first time. Then you learn how to win. I think this organization has really grown, especially since I've been here."

NOTES: Chicago Cubs 3B Kris Bryant finished with 99 RBIs, surpassing the club rookie record of 86 set by Billy Williams in 1961 and Geovony Soto in 2008. ... The Milwaukee Brewers were swept 10 times and went 16-34-4 in series play this season. ... The Cubs will travel to Pittsburgh for the National League Wild Card Playoff, set for Wednesday night at PNC Park. RHP Jake Arrieta (22-6, 1.77 ERA) will start for the Cubs while the Pirates will start their ace, RHP Gerrit Cole (19-6, 2.60 ERA).