PITTSBURGH -- There were fireworks on the riverfront in downtown Pittsburgh on Saturday night to celebrate the city's bicentennial and they just happened to coincide with an offensive explosion in the Pirates' fifth inning, highlighted by Josh Bell's first career grand slam in his second Major League at-bat.
Bell belted a pinch-hit grand slam and Andrew McCutchen drove in three runs, including a pair on a tie-breaking two-run single in the fourth, to lift the Pirates to a 12-6 victory and hand the Cubs their fifth straight loss.
"It's impossible to boat race the whole season like we were doing," Chicago's Anthony Rizzo said. "We just have to clean up our pitching a little. We're walking too many guys, and that's not the formula. We've had a formula of playing good baseball and we don't have it right now."
The Pirates pulled within 6 1/2 games of the Cubs in the National League Central, their smallest lead since May 31. Pittsburgh has won 12 of its last 15 games after its June slump. Chicago is now 6-15 since leadoff man Dexter Fowler went on the disabled list on June 19.

"We weren't walking away with our heads down, feeling sorry for ourselves," Pirates manager Clint Hurdle said. "We were getting beat through June, and we're not going to do backflips now. We're going to keep playing. The goal is to meet the demands of the game and play baseball at a very high level."
• Marte added to NL All-Star roster
Bell, promoted from the Minors on Friday, launched his home run with one out in the fifth off Adam Warren, and Jordy Mercer followed with a solo shot. McCutchen and Sean Rodriguez each hit solo home runs in the third off Chicago's Jon Lester, who was pulled after three innings.
• Recovering Fowler out of ASG
"I didn't see it getting better," Cubs manager Joe Maddon said of Lester's abbreviated outing. "He's going to be going to pitch a couple days from now [at the All-Star Game]. I thought Adam against that lineup there was a nice matchup one time through. ... It didn't play out that way."

MOMENTS THAT MATTERED
For whom the Bell tolls: Bell's first two Major League at-bats couldn't have gone any better. After hitting a single off Jake Arrieta Friday for his first hit, Bell's grand slam in his second at-bat gave the Pirates an 11-5 lead in the fifth. Bell crushed an 84 mph changeup to the top of the right-field bleachers. More >

Guess who's back?: As the Pirates surge, so, too, does McCutchen. Or maybe it's the other way around? McCutchen sent a solo homer to left field in the third to tie it, 4-4, and his two-run single an inning later gave the Pirates the lead for good. He has gone 5-for-9 with four RBIs this series and is hitting .313 in July after hitting .202 in June.

Start me up: Lester was named NL Pitcher of the Month in June, going 4-0 with a 1.41 ERA. But he served up eight runs over a career-low 1 1/3 innings against the Mets in his first start of July. In that game, he gave up three home runs. The Pirates hit two in the third inning -- solo shots by McCutchen and Rodriguez -- to go ahead, 5-4. Lester was pulled after throwing 64 pitches over three innings. The Cubs now do not have a quality start in nine games this month.
"We all go through times where, just like hitters, you go through slumps," Lester said. "You've got to figure out ways to contribute." More >

Opportunities: After Ben Zobrist launched a two-run homer with two outs in the first, the Cubs wasted a leadoff double by Javier Baez in the second. They came through in the third when Rizzo tripled and scored on Willson Contreras' infield single. Jason Heyward singled to chase starter Chad Kuhl, and one out later, Contreras scored from second on Baez's infield single off Juan Nicasio. Bryant and Rizzo hit back-to-back doubles in the fourth to tie the score at 5.

QUOTABLE
"I get goosebumps. I've got them probably a dozen times since I've been a coach or manager." -- Hurdle, on his reaction to Bell's grand slam
"We got off to such a wonderful start. You'd take this kind of lead going into the break any day of the week. [The recent struggles have] just happened, and there are reasons why it's happened. You don't lament those reasons, you deal with it, and keep going out and playing hard like we did and eventually we'll get back on a nice streak." -- Maddon, on the Cubs' recent struggles
SOUND SMART WITH YOUR FRIENDS
Rizzo went 4-for-5, falling a home run short of the cycle, although he came close in the eighth with an opposite-field double that bounced off the wall in left. The last Cubs player to hit for the cycle was Mark Grace, who did so May 9, 1993, at Wrigley Field. It was Rizzo's second four-hit game of the season; he also did so May 4 at PNC Park.
"It was close, really close," Rizzo said of his last at-bat against Jared Hughes. "He's got a big sinkerball so you don't try to do too much. I hit it well but just not well enough."

INJURY UPDATE
The Pirates lost second baseman Josh Harrison to left foot discomfort after he was hit by a pitch in the second inning. Right fielder Matt Joyce was pulled from the game in the sixth with left quad tightness. Both are day to day. More >

WHAT'S NEXT
Cubs:John Lackey will close the first half of the season with his first start of the season against the Pirates. He's 0-2 with a 7.56 ERA in his last three starts after opening the season 7-3 with a 2.78 ERA in 14 games. First pitch is scheduled for 12:35 p.m. CT. After the game, the Cubs' All-Stars will head to San Diego.
Pirates:Jonathon Niese will start against the Cubs at 1:35 p.m. ET in Pittsburgh's final game before the All-Star break. Niese is 3-8 with a 5.35 ERA in 12 career starts against Chicago. After the game, All-Stars Starling Marte and Mark Melancon will be San Diego-bound for Tuesday's All-Star Game presented by MasterCard.
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