Nelson started on Opening Day and Pacheco took the job when Nelson was injured early in the season. Now, Nelson is playing there regularly, because various injuries have necessitated that Pacheco move to first base.
"I played second for a little bit, now I'm playing third, so I'm just trying to produce each time I'm on the field," said Nelson, who went into Friday's start at third batting .279 overall and .281 with two of his six home runs in his 53 games at third.
The combined third base average should be higher. Nelson tried to play through an early-season wrist injury and saw his average dip to .219 before the Rockies placed him on the disabled list in May. Nelson also missed time between July 15 and Aug. 6 because of an irregular heartbeat, which he attributed to dehydration and overdoing energy drinks.
"It's just been being healthy and getting at-bats consistently the last couple of weeks," Nelson said. "I'm taking advantage of them."
Nelson's injuries gave Pacheco a chance to impress the Rockies with his ability to put balls in play. After Todd Helton underwent season-ending hip surgery and Michael Cuddyer suffered a right oblique strain that could cost him the rest of the year, Pacheco became the regular at first base. His position hasn't mattered. He went into Friday having hit safely in 16 of his previous 18 games. He entered Friday hitting .306.
Pacheco also has played briefly at catcher. However, Pacheco has appreciated being given long stretches at one position, rather than constantly having to prepare for something different.
"I don't like to focus on all three or four positions," said Pacheco, who batted .301 in 81 games at third and spiked to .340 in 16 games at first, where he started Friday. "I like to focus on one at a time and get better. It was nice to get a lot of reps at third base, and I feel I got better there.
"It's a little easier not having to make that throw, but there are a lot of other things to consider. You've got to know where to be on cutoffs. You've got to be able to pick a ball. Todd is unbelievable at that. I hope I can become half the defensive threat he is, especially when the guy is in the hole making tough throws."
The work of Nelson and Pacheco has made it unlikely that the Rockies will call up prospect Nolan Arenado from Double-A Tulsa when Major League active rosters can expand to 40 on Saturday. It was doubtful the Rockies would call Arenado up, regardless, since they aren't in a pennant race and Tulsa has qualified for the Texas League playoffs.
The Rockies have other reasons for not bringing up Arenado. By calling Arenado up, the Rockies would have to place him on the 40-man Major League roster a year ahead of when they'd have to do so by rule. The Rockies would also have one less spot to use this winter when they have to set their rosters. That spot could be the difference between protecting another prospect, or losing him to another club in the Rule 5 Draft.
Still, Nelson and Pacheco will enter next year with no guarantees. If the roster is healthy, it will be tougher to fit them both into a lineup.
The one weakness of this tandem is power. Pacheco has just two homers. Nelson appears to have more power potential, but 10 homers in two seasons -- shifting between second and third, with a little work at shortstop -- is not ideal for a corner position. Arenado, 21, who brings power, will be in Spring Training and could force his way onto the roster at some point.
Pacheco welcomes the competition.
"The mentality is not necessarily to beat somebody out, but to be the best player I can be," Pacheco said. "If you go into Spring Training worrying, 'What's he doing? What's he doing? What's he doing?' you're not going to prepare yourself physically and mentally to do what you need to do. The best 25 guys are going to be out there. So you prepare well enough and perform well enough that you're part of that 25."