CHICAGO -- Miguel Montero blasted a sixth-inning grand slam against his former team to blow open a tie game and help the Cubs to a 6-4 win and a sweep of the three-game series with the D-backs in front of a raucous crowd at Wrigley Field on Sunday. It was the fifth series sweep for the Cubs this season but their first three-game series sweep of the D-backs since 2012.
With the two teams locked in a 1-1 battle, Chris Coghlan led off the sixth with a single and Anthony Rizzo and Kris Bryant drew back-to-back walks to load the bases for Montero, who was traded from Arizona in December. D-backs manager Chip Hale brought in lefty Matt Reynolds to neutralize Montero, but he foiled the strategy with a grand slam to left that gave the Cubs a 5-1 lead.
"To be able to find a way back into that game, get on top and stay there, was huge," said Cubs manager Joe Maddon. "Give [the D-backs] credit, they're a really good team. It's an upcoming team, and they're going to be really good over the next couple years. You never let up on them."
The blast made a winner of reliever Justin Grimm (3-4) after Kyle Hendricks' five innings of one-run ball as the Cubs maintained a 7 1/2-game lead over the Nationals for the second National League Wild Card spot. Chicago trails the Pirates by three games in the race for the first Wild Card. D-backs starter Rubby De La Rosa (12-7) was charged with the loss.
"The ball was just up and away, [so] he was able to elevate it," D-backs manager Chip Hale said of Montero's homer. "He was trying to go fastball in to set up his breaking ball, and he just missed location and Miggy hit it well enough. Today we were looking at the flags, and we knew the ball was going to fly. Just can't make mistakes to good hitters."
The Cubs got their first hit and run in the fifth on Kris Bryant's 23rd homer of the year, a shot that hit the video board at the back of the bleachers in left-center.
"Good thing the board was there, otherwise [the ball] would still be flying," Montero said.
MOMENTS THAT MATTERED Go deep, young man: Arizona left fielder David Peralta didn't budge from his spot as Bryant's home run flew over his head. The 23-year old's homer was projected by Statcast™ to travel 495 feet from home plate, the longest in the Major Leagues this season. In the process, Bryant tied Billy Williams and Geovany Soto for the club's single-season rookie RBI mark with 86.
"As baseball players, you just want to get a hit every time," Bryant said of his blast. "When you have two strikes, you kind of shorten up and try to put it in play, so that's all I was trying to do there." More >
Running into outs: It was not a great day for the D-backs on the basepaths as they were doubled off twice and caught stealing twice. A.J. Pollock was caught stealing second in the first inning, and Ender Inciarte was stealing in the fifth when Cubs starter Kyle Hendricks threw to first, resulting in another caught stealing. Peralta was doubled off first on Castillo's liner in the second, and Pollock was doubled off first in the sixth on Paul Goldschmidt's lineout to right.
"Again we hit a lot of balls well right at some guys," Hale said. "We hit into some tough luck with the steals and the double plays."
Sixth-inning power: Montero's grand slam wasn't the only long ball in the sixth inning, as pinch-hitter Jonathan Herrera got in on the action. Herrera took the first pitch he saw from Silvino Bracho to right field for his second homer of the season, and the first pinch-hit homer of his career.
After Montero received a curtain call, Herrera couldn't help going up for one of his own, with the apparent support of a laughing Anthony Rizzo.
Rallying late: The D-backs made things interesting in the ninth with some home runs of their own. Welington Castillo, who had an RBI double earlier, started it with a one-out homer to center, and after Chris Owings drew a two-out walk, Nick Ahmed hit a Pedro Strop pitch into the bleachers in left-center to pull the D-backs to within 6-4.
"He's come through in some really large moments for us. He's got some big hits. He's very active behind the plate, very vocal on the bases. He's a big part of the fabric of what we're doing." -- Maddon, on Montero
SOUND SMART WITH YOUR FRIENDS
The Cubs have hit a home run in 15 consecutive games at Wrigley Field. It's the first time Chicago has done so since 1991. The Cubs have 39 homers over their last 15 home games, equalling a club record in that span.
WHAT'S NEXT D-backs: Arizona returns home Monday to open a three-game series with the Giants at 1:10 p.m. MST. It is the beginning of a nine-game homestand that includes visits by the Dodgers and Padres. Patrick Corbin, who is 1-0 with a 2.19 ERA in his last two starts, will get the start.
Cubs: Chicago begins an 11-game road stretch when it faces NL Central-leading St. Louis on Monday. Dan Haren takes the mound in search of his first quality start since July 30, when he was with the Marlins. First pitch is scheduled for 1:15 p.m. CT.
Greg Garno is an associate reporter for MLB.com. Steve Gilbert is a reporter for MLB.com. Read his blog, Inside the D-backs, and follow him on Twitter @SteveGilbertMLB. This story was not subject to the approval of Major League Baseball or its clubs.