Francisco Liriano will try to lead the Pirates to their first three-game sweep at Wrigley Field in 13 years Wednesday ahead of a pivotal season-ending series.Pittsburgh (91-67) arrived in Chicago having lost five of seven and Sunday's 11-3 drubbing to Cincinnati cost the Pirates sole possession of the wild-card lead. They've bounced back with two victories over the Cubs (65-93) and an 8-2 rout Tuesday helped them move a game in front of the Reds.Pittsburgh also stayed within two games of St. Louis in the NL Central with four contests remaining for both clubs. After wrapping up its stay in Chicago, Pittsburgh will head to Cincinnati for its final series."We're still trying to win our division. That's what we're shooting for, so we're trying to win out here and just keep going for the next four games," star outfielder Andrew McCutchen said.Liriano (16-7, 2.88 ERA) will try to help his club with another impressive outing against Chicago. He's 3-0 with a 1.24 ERA in four matchups this season and 2-0 with a 1.13 ERA in his two at Wrigley Field.Liriano gave up two runs in six-plus innings to the Cubs on Sept. 15, but did not get a decision in a 3-2 win. Five days later, he yielded two runs and three hits in eight innings of a 6-5, 10-inning loss to Cincinnati."(Liriano) was fantastic," manager Clint Hurdle said.Liriano has been seeking to become the first Pirates pitcher with at least 17 wins since John Smiley went 20-8 in 1991. He'll also try to lead Pittsburgh, 12-6 in this season's series with the Cubs, to their first three-game sweep at Wrigley since May 5-7, 2000.The Cubs' Jake Arrieta (3-2, 3.94), meanwhile, will likely head into his final start of the season with a more modest goal.The right-hander is hoping to finish strong after a stellar outing in Milwaukee on Thursday. He yielded a solo homer and two other hits in seven innings of a 5-1 victory."I want to be one of those guys who some young guys look at and say, 'This guy knows how to do it the right way.' It's just a matter of keeping that hungry mindset and rolling that over into next year," he told the team's website. "We're out of it, but a lot of good things can happen next year. Guys can show they're hungry for a winning team. If we're all on board with that, we're going to be good going into next year."Arrieta is 2-0 with a 3.71 ERA in three career starts against Pittsburgh but did not get a decision in a 5-4 win Sept. 13. He gave up four runs in five-plus innings, including three solo homers in the fourth, in his lone matchup this season.McCutchen had two hits off Arrieta in that game and is 4 for 9 in his career against him.Anthony Rizzo (0 for 11) and Darwin Barney (0 for 12) have struggled mightily against Liriano, and Starlin Castro is 2 for 14 in his career versus the left-hander.