"I have a lot of respect for Jay's basketball acumen," Colangelo said. "He will be a fresh voice for the players to listen to."
"It is a little bittersweet," Triano said. "Sam gave me the opportunity to work with him and was great to work with.
"When you're together for 3½ years, as well as being coaches, you become friends. But it is an opportunity and I look forward to moving forward and seeing what we can do with this basketball team."
Mitchell posted a 156-189 record with Toronto, but the Raptors sit an unremarkable 8-9 this season, one in which they expect to be a contender in the Eastern Conference.
"Are we getting the most out of this roster every given night?" Colangelo said. "That is what we're seeking to improve."
Tuesday's embarrassing 132-93 loss at Denver was Toronto's fourth in the last six games, the fifth-worst in team history and, ultimately, Mitchell's undoing.
"It is safe to say that after the debacle that we all witnessed last night against Denver, a 39-point loss, not to mention several other incidents this early season where we gave up double-digit leads or had mental breakdowns, with respect to the effort on the court, you come to a point where you realize some of the things you want to see out on the court are not taking place," Colangelo said.
Mitchell elected not to lash out at the players following Tuesday's setback, preferring to let them discuss it among themselves.
"For me, now, it is not a time to be screaming and yelling," Mitchell told reporters outside the locker-room. "It is a time to be trying to teach and reassure people."
Chris Bosh, Jose Calderon and newcomer Jermaine O'Neal reportedly chaired the players' meeting.
"It is embarrassing not only for us, but for those who support the Toronto Raptors, the organization, the city and the country," O'Neal said. "That should never happen.
"This is a business, we get paid a heck of a lot of money to play a certain way. If we think we can turn it on and off like that, then we're fooling ourselves."
The outcome in Denver revealed more warts than Colangelo felt comfortable with: a stagnant offence; a porous defence; and something rarely seen in Mitchell's tenure — a lack of commitment from the players.
"You get a sense when people are being heard or disregarded," Colangelo said. "I have to say Sam has always had a relationship with the players.
"There comes a time when you feel that the best way to improve a situation is to make a change at the top and a change in the voice."
'It is time to make a coaching change'
Mitchell was chosen the NBA's coach of the year in 2007, when the Raptors went 47-35 and clinched their first Atlantic Division title and their first playoff berth in five seasons.
Toronto's 47 wins that season equalled the franchise record and represented a 20-win improvement over the previous season, when it managed a 27-55 mark under Mitchell.
Colangelo promptly re-signed him to a four-year, $12-million US contract on May 22, 2007.
Prior to that, Mitchell was the lowest paid head coach in the league at $2 million US per season.
Mitchell's engaging personality made him a instant favourite with the fans, the media and even the players.
But too often the Raptors looked to be spinning their wheels.
"It comes down to an entire body of work that you study," Colangelo said. "You look at all the circumstances that may have gone into our failures and there comes a time when you can honestly say it is time to make a coaching change and that realization was met over a period now of a couple of weeks with finality of [Tuesday] night after the game."
Mitchell replaced Kevin O'Neill as Toronto's sixth head coach on June 29, 2004.
Mitchell spent two seasons as an assistant coach with the Milwaukee Bucks prior to joining Toronto.
He also was hired to be Bernie Bickerstaff's lead assistant with the Charlotte Bobcats, who granted him permission to talk to the Raptors.
With files from the Canadian Press