CHICAGO -- Mike Montgomery got support from Anthony Rizzo at the plate and Javier Baez in the field, and they combined to power the Cubs to a 6-1 victory Monday over the Pirates.
With the win, the Cubs opened a 2 1/2-game lead over the idle Brewers in the National League Central. Rizzo hit a double, scored a run and added a sacrifice fly to help the Cubs become the fifth NL team to reach 70 wins.
Montgomery was making his second start subbing for Jonathan Lester, who is on the disabled list, and threw seven scoreless innings in his longest outing since he threw a shutout June 30, 2015, against the Padres. The lefty served up Jordy Mercer's 12th home run to open the Pirates' eighth and was lifted. He admitted to being nervous on the day he starts but then settles down.

"I've been in different roles this year," said Montgomery, who subbed earlier this season and was making his 10th start of the year. "You've got to look at it and say, 'Hey, I get to start for the Chicago Cubs and it's going to be a fun day.'"
"His future is as a starter," Cubs manager Joe Maddon said. "What you saw tonight is typical of what he's capable of doing over a long period of time."
• Montgomery showing strong future as starter

Rizzo doubled to lead off the second and scored on Ian Happ's single, then added his sacrifice fly in the fifth. Both runs came off the Pirates' Trevor Williams, who was coming off an impressive start against the Dodgers in which he threw eight shutout innings. On Monday, the right-hander struck out four over five innings, including Rizzo and Happ back to back to end the Chicago third and strand two runners.
"Just not hitting the panic button," Williams said. "These guys can put up crooked numbers on you quickly. Montgomery was throwing great for them, so you know it's going to be a low-scoring game. I had to keep it within grasp for our guys."
• Pirates expecting more from offense
Rizzo is now batting .415 (22-for-53) with 22 RBIs and 14 runs scored in his last 14 games.
The Cubs took advantage of two errors in the seventh to pad their lead. Chicago loaded the bases with two outs and Alex Avila hit a single that second baseman Sean Rodriguez fielded but overthrew Josh Bell at first. Avila was credited with one RBI, and another run scored on Rodriguez's miscue. A third baserunner scampered home on catcher Chris Stewart's errant throw into center.
"If there's a play to be made, we like to think we could make it," Pirates manager Clint Hurdle said. "If not, we still could contain the ball and we only give up one run. However, that didn't happen."

Avila just took advantage of the moment.
"I knew it would be a tough play for [Rodriguez]," Avila said. "The spin took him. As soon as I saw the ball take off behind Bell, I took off, not even concerned about where the ball was going or if Stewart was going to be able to cut it off. I thought if I run hard, I could draw the throw."
MOMENTS THAT MATTERED
Exit velocity: It's not how hard you hit the ball but where it goes that matters. Montgomery led off the Cubs' fifth with an infield single that, according to Statcast™, had an exit velocity of 31.7 mph. One out later, he reached third on Thomas La Stella's single and Kristopher Bryant walked to load the bases for Rizzo, who launched a fly ball to center that had an exit velocity of 99.6 mph. Andrew McCutchen caught it at the wall for a sacrifice fly, and Montgomery scored to open a 2-0 lead.
"I'll take any hit I can get," Montgomery said. "I'm not worried about [exit velocity]."
Glovework: Montgomery got help from shortstop Javier Baez, who made a sliding stop to grab Jose Osuna's grounder and get to his feet in time to throw him out and end the third. With a runner at first and one out in the Pirates' fifth, Baez caught Stewart's liner and tagged the runner for a double play.
"The play in the hole [on Osuna] was outstanding," Maddon said. "[Baez] was so deep in the hole -- he was on the grass about 10 feet it looked like. It was awesome."
Said Montgomery: "That just gives me such a boost knowing I've got guys diving around for me, making big plays."

Avila has been impressed by the Cubs shortstop.
"His athleticism, his arm allows him to do that," Avila said. "You don't teach those things. That's God-given talent. He's been able to put it together. You see those plays but the work that goes into it -- being in the right spot, having a good first step, anticipating the ball, all of that gets you the result you're getting from him. He has the athleticism and wherewithal to make the spectacular plays. He's been picking everything over there."

QUOTABLE
"I thought he got it. Out of the hand, I thought I hung it enough. But I sleep really easily at night knowing Cutch is patrolling center field for us. He made a hell of a play." -- Williams, on McCutchen tracking down Rizzo's fly ball in the fifth inning

SOUND SMART WITH YOUR FRIENDS
The Pirates have not scored a run behind Williams in his last 13 innings. Williams pitched eight shutout innings against the Dodgers on Wednesday opposite Rich Hill, who worked nine hitless innings.
WHAT'S NEXT
Pirates:Chad Kuhl will start for the Pirates as they return to Wrigley Field on Tuesday night to face Jacob Arrieta and the Cubs. Kuhl ran up a high pitch count and lasted only four innings against the Dodgers on Thursday, but he has put together a 3.30 ERA over his last 11 starts. First pitch is scheduled for 8:05 p.m. ET.
Cubs: Jake Arrieta will make his 27th start of the season Tuesday. In his last outing against the Reds, he gave up one unearned run over 5 2/3 innings, ending a streak of seven straight quality starts. He's 5-1 with a 1.78 ERA in his last eight outings. First pitch is scheduled for 7:05 p.m. CT from Wrigley Field.
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