However one, or both, could soon be watching a match from the sidelines.
Head coach Oscar Pareja is debating when would be the right time to give both workhorses a week off.
"We have. And actually at this moment, and this week, we are thinking about it more than before," Pareja said after Tuesday's training. "Because there is an accumulation of minutes and games. With Brian, for example, we want to manage him well, but at the same time, we don't want to mess much with the lineup. You have to kind of balance that, but it's a factor for us all the time."
The Rapids (4-4-3, 15 points) are on a run of positive results, going 4-1-2 over the last seven matches ahead of Saturday's match at San Jose with Mullan at right back and Powers adding two goals from midfield.
Pareja added that the staff has noted a difference in defender Drew Moor after he was forced to sit while serving a two-game suspension in April.
"It showed us that when Drew had a break, that break actually helped him," Pareja said. "He rested and came back sharp, and is he's playing his best now."
Only seven field players in MLS have played more minutes than the 35-year-old Mullan, who has played every minute of all 11 matches (990 total). No rookies have played more than then 930 minutes Powers has played.
"The young guys have the willingness, the desire, the passion but normally they don't have the experience to know when to push and at some point they hit a wall," Pareja said of Powers. "And they're not going to come to you and say, 'hey I'm tired.' They are going to keep going. And we need to see them and start noticing when they need a break."
The team heads California on Friday ahead of Saturday's match against the Earthquakes (3-4-5, 14 points), which will be shown live at 8:30 p.m. MT on Altitude TV.