De La Rosa and starter Wilin Rosario got their signals crossed in the season opener at Miami, leading to De La Rosa's temper triggering in what turned into a five-run inning, chasing the Rockies' ace from the game.
"It has as much to do with certain matchups," manager Walt Weiss said of the decision to start Pacheco, downplaying any difficulty between De La Rosa and Rosario. "Also, [Sunday] being a day game, I want to scatter certain guys so it's not wholesale changes all on one day.
"Wilin has had some success against [Sunday starter Wade] Miley. He was going to get one of the days off, and he swings the bat well against Miley. It comes down to just picking my spot with Wilin. But Jordan's not De La's personal catcher."
Part of Weiss' challenge is to keep his team fresh during a season-opening stretch in which the Rockies play 40 games in 42 days.
"It's a tough schedule," Weiss said. "It's a tough league. You're always going to have tough stretches. We got one right out of the gate. I'll pay attention to the workload the guys are getting and try to look at the long haul and balance it out with trying to win the game that day and try to make the best decisions."
One of the turnarounds Weiss made in helping to improve the Rockies' win total by 10 games between 2012 and 2013 was reverse a dismal record on Sunday, when the Rockies in 2012 struggled with lineups featuring multiple reserves.
"Last year, our backup guys did really well," Weiss said. "Our Sunday record last year was over .500. It's all a balance like everything else. Keep the picture in mind that you're trying to win that game."
Owen Perkins is a contributor to MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.