DENVER -- Nolan Arenado emphatically ended his slump and his slugging drought Sunday with a four-hit game that included a memorable power display.

He hit two three-run homers as the Colorado Rockies piled on the Chicago Cubs for seven runs in the first inning and rolled to an 11-4 win in the rubber game of the three-game series.

"It worked out today, and I'm very happy about that because it's been hard," said Arenado, who went 4-for-5 with six RBIs, one shy of his career high set on April 13. He tied his career high with four hits. "I just want to help the team win, and I feel like I haven't done that the way I know I can."

The Rockies won for the fourth time in five games as they finished a 4-2 homestand against the Cubs and Washington Nationals, both division leaders. The loss was just the fifth in 24 games for the Cubs.

Arenado hit a three-run homer in the first when the Rockies abruptly ended Jason Hammel's 22-inning scoreless streak. In the fourth, Arenado belted another three-run homer off Hammel (13-6), who had gone 6-0 with a 0.95 ERA in six starts since the All-Star break.

"A lot of foul balls today off my slider and two mistakes to Arenado," said Hammel, who gave 10 hits and 10 runs (six earned) in 3 1/3 innings. "That was pretty much the story. We'll forget about it, it's not going to bother me. I was pitching great up until this point, and it's one of those outliers and we will just move on."

Arenado entered the game with three hits in his past 30 at-bats, a tailspin that had dropped his average to .275, the lowest it had been since he was hitting .274 on April 25. He had gone 12 games without an extra-base hit since his last homer Aug. 8.

Entering Sunday, Arenado was hitting .242 (30-for-124) in 34 games since the All-Star break with seven homers, 28 RBI and a .767 on-base-plus-slugging percentage. Before the game, manager Walt Weiss was asked about Arenado's extended slump and answered with humor and insight.

"I don't worry too much about him, just try to find a way to hide the sharp objects because that's kind of how he's wired," Weiss said. "But he'll find a way to work himself out of it."

After Saturday night's game, Arenado said he and batting practice pitcher Garrett Carson worked in the indoor cage, watched video and even argued a bit about Arenado's situation.

Arenado said Carson insisted there was not much off with the third baseman's swing. The third baseman felt otherwise, and he and Carson kept at it and ultimately Arenado left Coors Field content.

"After last night, I was able to sleep better after what I worked on, and I applied it today and it worked out" Arenado said. "Not overstriding, staying back and trying to see the ball. My hands felt fast today, and that means my body wasn't getting in the way of my swing."

Arenado's six RBIs gave him a major-league-leading 104, and he took over the National League lead with 32 homers.

Jorge De La Rosa, who had no-decisions in each of his previous three starts, all Rockies losses, worked a career-high-tying eight innings and got 13 outs on ground balls. He held the Cubs to four hits and two runs on two solo homers by Addison Russell. De La Rosa (8-7) struck out six and walked one.

"Everything was working really good," De La Rosa said. "Curveball, changeup, fastball. Good location, too. They were really aggressive, and I just tried to keep the ball down."

For the second time in four games, the Rockies scored seven runs in the first. On Wednesday, they needed to hold off the Nationals for a 12-10 win. On Sunday, De La Rosa went out and set the Cubs down in order in the second and again in the third.

"It was huge," Weiss said. "We let the Nationals sneak back into the game and we had to grind to the finish line."

The Cubs aided the Colorado cause with three errors in the first, two of them resulting in four of the runs being unearned.

Arenado's one-out homer drove in David Dahl and DJ LeMahieu, who began the inning with singles. First baseman Anthony Rizzo botched Gerardo Parra's grounder. After Daniel Descalso walked, third baseman Kris Bryant threw wide of second base on Ben Paulsen's grounder to load the bases.

Tony Wolters doubled home two runs, making him 5-for-7 with three doubles, one triple and 12 RBIs with bases loaded. De La Rosa followed with a two-run single.

"An oil painting, it was not," Cubs manager Joe Maddon said. "We gave them too many opportunities, and we made Jason have to get six outs (in the first inning). We started making too many mistakes, and we put Jason behind the proverbial eight-ball. So he was not good, I agree, but I think it could have been a little bit different shading to it had we just caught the ball."

NOTES: Rockies CF Charlie Blackmon was not in the lineup for the third straight day but said his bruised right big toe was better. He could start Monday at Milwaukee. ... Cubs OF Jorge Soler was scratched from the lineup due to soreness in his right knee but pinch-hit in the ninth. ... Rockies RHP Jeff Hoffman was the seventh Colorado player to make his major league debut this season, joining RHP Matt Carasiti, RHP Carlos Estevez, LHP Tyler Anderson, SS Trevor Story, C Tony Wolters and OF David Dahl. ... The Rockies went 4-2 against the Cubs this season.