The Red Devils manager restated his decision on Saturday was based purely on a desire to shield Rooney from what he thought would be a venomous attack from the home supporters at Goodison Park.
But, on home soil, Rooney will be let loose on the Scottish champions in Tuesday night's Champions League Group C opener.
"I have no regrets - I did the right thing," said Ferguson.
"And I have no concerns about playing him tomorrow at all."
There have been suggestions since Saturday's 3-3 draw that Ferguson left Rooney out as punishment over the off-field allegations that have been made against him.
However, the United boss insists that version is not true.
"I have no need to clear it up," he retorted.
"I explained the reasons on Saturday. There is nothing beyond that.
"I don't know if tomorrow will inspire him. He has a lot of experience behind him.
"But I do know scoring for England last week will have given him a boost."
As a former team-mate of Rooney from their days at Everton, Rangers captain David Weir knows the 24-year-old well.
And he feels if the Rangers fans have any intention of trying to make life uncomfortable for Rooney, they would be better served not bothering.
"I am more interested in Wayne Rooney as a footballer and I don't think there is any need to give him any encouragement," said the veteran defender.
"He is one of the best players in the world."
Weir still remembers seeing Rooney breaking into the Everton first-team set-up and what an impact he made.
"He was only 16 but he took to it like a duck to water," he said.
"He scored some great goals; some famous goals like the one against Arsenal that launched his career.
"Since then he has gone from strength to strength.
"Everyone loved him and it is great to see him doing so well, although I am not sure having played with him will give me any kind of advantage tomorrow."
Rangers manager Walter Smith had left Goodison Park before Rooney made his big first-team breakthrough, having been denied the chance to play him because of his age.
"We weren't allowed to do it," recalled Smith.
"But he was an outstanding young player - the best I have seen in my own career.
"There is no doubt he has made his mark in football already and he has a tremendous amount of football to play in future."