CHICAGO -- As hard as he is for opposing hitters to figure out, Gerrit Cole insists he is taking a simple approach on the mound.
"There's a lot of extra noise that happens in September and I think the simpler you can keep things the better it is," Cole said.
Pittsburgh increased its lead for the NL's top wild card to 4 1/2 games over the Cubs, who would have secured their first postseason appearance since 2008 with a victory. Chicago would clinch with a loss by San Francisco to Oakland on Friday night.
Cole (18-8) and Lester (10-12) each lasted seven innings, and Mark Melancon held off a rally attempt in the ninth for his major league-leading 51st save in 53 chances.
Cole's 18 wins are the most for a Pirates pitcher since John Smiley went 20-8 in 1991. Cole gave up two runs and five hits, struck out eight and walked two while improving to 7-1 in nine starts against Chicago.
"I know that he's got a competitive chip that's special," manager Clint Hurdle said. "When you combine that with a very elite skill set and a desire to be `the guy.' He's shown that ability in September."
He also drove in the game's first run with a single in the third.
Michael Morse put Pittsburgh ahead 2-1 with an RBI single off Lester in the seventh. The Pirates added a run in the eighth against Pedro Strop when Jordy Mercer reached on a wild pitch as he struck out leading off and scored from third on a grounder by Starling Marte.
Lester allowed two runs and five hits.
"Great game," manager Joe Maddon said. "As a baseball fan, you were totally entertained. That's what it's supposed to look like."
Kris Bryant had two hits and scored, but Chicago came up short after winning seven of nine.
With a 12:05 p.m. CDT start Saturday, Maddon was not planning to stay up for the Giants game. He said the only way he would check the score "probably when I get up to go to the bathroom at night."
Asked how the Cubs might celebrate, Maddon said, "Maybe via text."
Cole gave the Pirates a 1-0 lead in the third with a single past a diving shortstop Addison Russell after Jordy Mercer doubled.
The Cubs tied it in the fourth when Bryant led off with a single and scored from third on a force by Addison Russell.
It stayed that way until the seventh, when former Cub Aramis Ramirez led off with a double and scored on Morse's one-out single. Morse, who was running on the pitch, then got doubled off on Josh Harrison's pop fly to first to end the inning.
NO ILL INTENTION
Coghlan insisted he wasn't trying to injure Jung Ho Kang with a takeout slide at Pittsburgh last week that left the Pirates shortstop with a broken left leg and torn knee ligament.
"I hate that he misses the whole year and it's a significant injury and a big blow to them," Coghlan said. "But I think those guys over there understand the way I play and it wasn't a dirty play."
Pirates: LHP Francisco Liriano (11-7, 3.41 ERA), coming off a win over Clayton Kershaw and the Los Angeles Dodgers, looks to stay on a roll for Pittsburgh. He is 7-1 in his past 15 starts, with the Pirates winning all but one of those games.
Cubs: With a 5.77 ERA over his last 11 starts, RHP Jason Hammel (9-6, 3.79) looks to break out of his slump.
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