PITTSBURGH -- Already off to their best start in more than 100 years, the Cubs further cemented their status as the National League Central's team to beat on Wednesday, finishing a three-game sweep of the Pirates with a 6-2 win at PNC Park.
Lefty Jon Lester worked out of two jams to hold the Pirates scoreless for 5 2/3 innings and displayed some nifty glove work, Ben Zobrist ripped a three-run homer and the Cubs improved to 20-6 on the year, six games ahead of the second-place Pirates. Pittsburgh has lost four in a row, and the Bucs' starting pitching continued to struggle in Wednesday's series finale.
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"We got out-executed across the board the last three days," Pirates manager Clint Hurdle said.
Coming off a strong seven-inning start, Pirates right-hander Juan Nicasio plodded through 4 1/3 innings, allowing four runs (one earned) on eight hits and three walks. Andrew McCutchen committed a crucial error, losing control of an Anthony Rizzo line drive, before Zobrist's second homer of the season, a three-run shot in the third inning.
"I feel like we constantly put pressure on the other team," Cubs catcher David Ross said. "I don't think we're waiting for our break, obviously that's what you are striving to do, is play clean games. We get a little break there and the three-run shot by Zobrist."
The Cubs have outscored their opponents this season by 93 runs, 159-66, by far the highest total in the Majors. They outscored the Pirates in this series, 20-5.
"These past three, we had opportunities, but we didn't play our best baseball," McCutchen said. "We can all look at that and know it wasn't the type of baseball we played prior to coming here. That's all it is. We've got to be better coming through in big, key situations."
MOMENTS THAT MATTERED
Great escape: Lester did some masterful pitching to escape a no-out, bases-loaded jam in the fourth inning. He struck out Sean Rodriguez, got Josh Harrison to fly out to right and struck out Gregory Polanco to end the threat. He pitched out of trouble again in fifth inning, getting a big strikeout of Starling Marte.

"Obviously, not the situation I wanted to put myself in, especially two starts in a row," Lester said. "But we got out of it and tried to take the positives from it."
Another memorable out came in the bottom of the second. Francisco Cervelli hit a comebacker that got stuck in the web of Lester's glove. So the lefty improvised and threw his entire glove to first base for the out.

Third out, in and out: With two outs and one on in the third, Rizzo ripped a line drive to center field. McCutchen charged in on the ball and caught it as he slid, but the ball bounced out of his glove after he landed, allowing Rizzo to reach safely. One pitch later, Zobrist launched a three-run homer.

"He smoked it," McCutchen said. "It was a knuckleball. I did what I could to try to catch it. I did everything I could to try to catch it. When my glove hit the ground, it popped out. Tried to catch it, that's all you can do."
Rizzo raking: Rizzo homered off Ryan Vogelsong to lead off the seventh inning, his ninth home run of the year and his 27th RBI.
The Cubs' first baseman has six homers and 16 RBIs over his past 12 games, with at least one RBI in 10 of those 12 games.

Re-Joyce:Matt Joyce continued his impressive turnaround at the plate, crushing a two-run homer to right field off Cubs reliever Adam Warren in the seventh inning. It was Joyce's Major League-leading third pinch-hit home run and his fourth overall.
QUOTABLE
"Just keep pushing. That's what we do. We're never going to let one game or one series affect what we do as a group. It's baseball. Teams don't go 162-0." -- Harrison
"We'll hit the reset button. Off-day comes at a good time." -- Hurdle
SOUND SMART WITH YOUR FRIENDS
This was the Cubs' first sweep of the Pirates since September 2012, when they swept the Bucs in a three-game series at PNC Park.
REPLAY REVIEW
With one out in the fifth inning, Pirates leadoff man Jordy Mercer hit a grounder to shortstop Addison Russell and was ruled out at first base. Pittsburgh challenged the call, and after a 2-minute review, the call was overturned and Mercer was ruled safe. The Pirates retained their challenge.

WHAT'S NEXT
Cubs: The Cubs return to Wrigley Field and open a four-game series with the Nationals on Thursday at 7:05 p.m. CT. Right-hander Kyle Hendricks, 1-2 with a 3.52 ERA so far this season, will make his fifth start of the year for the Cubs.
Pirates: After a day off to travel Thursday, the Pirates will begin a three-game series against the Cardinals at 8:15 p.m. ET Friday. Left-hander Francisco Liriano will start against St. Louis, as he did on Opening Day, and third baseman David Freese will play at Busch Stadium for the first time as a visiting player. The Bucs and Cards have split their last 60 games evenly, with 30 wins each.
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