The Cubs loaded the lineup with left-handed hitters against Rockies southpaw Jorge De La Rosa because they wanted the at-bats.
"They need to see them, and they'd like to see them," Chicago manager Rick Renteria said. "It's been asked many times, 'Is it conducive for a left-handed hitter to face left-handed pitching, to see if it helps?' And this is one of those instances where we'll have the opportunity to do that and will take advantage of it."
Nate Schierholtz, Anthony Rizzo, Ryan Sweeney and Luis Valbuena were hitless against De La Rosa, although Valbuena did draw a walk in the third. The Rockies starter gave up two hits and struck out one over three innings.
"I'm still working on my fastball command, working both sides of the plate," said De La Rosa, who will likely be the Rockies' Opening Day starter. "My changeup was much better today than the last two games. ... I'm just trying to work on some things now, but when I'm in trouble, I pitch like it's a game."
Corey Dickerson singled with one out in the first against Chicago's Travis Wood and scored two batters later on Drew Stubbs' single.
With two outs in the Rockies' third, Arenado was credited with a triple on a ball that center fielder Junior Lake lost in the sun. Parker followed with his first home run for a 3-0 lead, and Stubbs singled and scored on Michael McKenry's double. Josh Rutledge smacked an RBI single to open a 5-0 lead, and Wood gave up a single to Jordan Pacheco before he was lifted. Wood was charged with five runs on nine hits and one walk over 2 2/3 innings.
Jordan Lyles, who is competing for a spot in the Rockies' rotation, gave up two hits and struck out four over three innings in relief.
Colorado had runners at second and third with two outs in the sixth against Hector Rondon and added another run on a passed ball by catcher Welington Castillo. Arenado then belted his first spring home run off a 2-2 pitch to left. Matthes added a three-run homer in the Rockies' seventh off Rondon, and Wheeler clubbed a massive two-run blast in the eighth off reliever Chang-Yong Lim.
Up next: James McDonald will make his second spring start on Wednesday, when the Cubs travel to Peoria, Ariz., to face the Mariners in a rare night game (9:05 CT). McDonald, 29, had a tough time last season with the Pirates. He was limited to six games because of shoulder issues and posted a 2-2 record with a 5.76 ERA. Pittsburgh designated him for assignment in September and outrighted him to Triple-A Indianapolis, but McDonald refused the assignment and elected free agency. Fans can listen to an exclusive webcast on cubs.com and watch on MLB.TV.