CHICAGO (AP) It's just not Kris Bryant's style to watch his home runs - even when he's launching a rocket nearly 500 feet off a gigantic video board.
Bryant hit a huge home run and tied a club rookie record for RBIs, Miguel Montero added a grand slam, and the Chicago Cubs beat the Arizona Diamondbacks 6-4 to complete a three-game sweep Sunday.
Bryant's drive leading off the fifth against Rubby De La Rosa (12-7) traveled an estimated 495 feet.
''I knew I hit it good,'' he said. ''No reason to watch.''
''It's just never been part of my game,'' he said. ''I don't believe in showing up your opponent.''
The home run also gave Bryant 86 RBIs, tying a club rookie mark held by Hall of Famer Billy Williams (1961) and Geovany Soto (2008), and wiped out a 1-0 deficit.
Montero connected against Matt Reynolds in a five-run sixth. Pinch-hitter Jonathan Herrera added a solo drive off Silvino Bracho in the inning to make it 6-1, sending Chicago to the victory.
The schedule is about to get tougher for the Cubs - tops in the National League at 26-10 since July 29 - with three games at Central leader St. Louis starting Monday. But they did exactly what they wanted in this series after dropping six of eight.
Former Cub Welington Castillo had three hits, including an RBI double in the fourth and a solo home run in the ninth. Nick Ahmed added a two-run drive off Pedro Strop in the inning before Phil Gosselin struck out, giving the Diamondbacks 11 losses in 14 games.
De La Rosa gave up three runs and five hits in five innings.
''I do think our guys are giving really good effort,'' manager Chip Hale said. ''We hit a lot of balls well, right at some guys, tough luck with the steals and the double play. We're probably not pitching well enough in the bullpen to be a winning ballclub. We have to have a little better at-bats. It's not from lack of effort.''
Justin Grimm (3-4) picked up the victory with a scoreless inning in relief, and Kyle Hendricks remained winless since Aug. 8. He held Arizona to just one run and three hits before being lifted for a pinch hitter in the fifth.
The Cubs did not get a hit until Bryant connected on an 0-2 pitch leading off the fifth. That gave him 23 homers - two shy of Williams' franchise rookie mark.
''Good thing the board was there,'' Montero said. ''Otherwise, it would still be flying right now.''
Montero's grand slam was the third of his career and the fifth by the Cubs this season, matching their highest total since 2009. Chicago hit seven in 2008.
Diamondbacks: The Diamondbacks hope 2B Aaron Hill can return to the starting lineup by midweek. Hill still has a ''tweak'' in his hamstring, which he pulled Tuesday, manager Chip Hale said.
Cubs: Manager Joe Maddon is not completely ruling out OF/C Kyle Schwarber (rib cage strain) for the series against St. Louis, although he does not anticipate him playing. Schwarber was out of the lineup for the fourth consecutive game. ''We'll see what he feels like when he gets to the ballpark tomorrow,'' Maddon said. ''I'm anticipating not being able to use him, but if we are able to use him, that'd be great.''
Diamondbacks: LHP Patrick Corbin (4-3, 3.67 ERA) starts as the Diamondbacks face RHP Mike Leake (9-7, 3.49) and the San Francisco Giants.
Cubs: RHP Dan Haren (8-9, 3.89) looks to put aside his struggles as the Cubs face RHP Lance Lynn (11-8, 2.80) and the Cardinals. Haren is 1-2 with a 5.87 ERA in six starts since the Cubs acquired him from Miami on July 31.