Two sources with knowledge of his campaign say former Saskatoon mayor Don Atchison will announce a comeback bid for the mayor's seat on Friday.

Atchison will make an announcement at 10 a.m. Friday at Rotary Park, according to a Thursday news release from his campaign team. The release did not specify what Atchison will announce.

Atchison lost to current Mayor Charlie Clark in 2016 by over 3,000 votes. He served as mayor from 2003 to 2016, making him the city's longest-serving mayor.

More recently, Atchison has worked as a senior consultant for Canwest Commercial Land Corp., which has proposed building a world trade centre tower in downtown Saskatoon.

Atchison's entry into the 2020 mayoral race would make for an even more crowded field.

Five people, including Clark, have already entered the race. The other four are businessman Mark Zielke, planner and architectural technologist Cary Tarasoff, professional engineering consultant Zubair Sheikh, and former SaskParty cabinet minister Rob Norris.

Clark's campaign team said he would respond after Atchison's speech on Friday.

Rumours of Atchison's return have swirled for a while. Norris said in April that he'd heard murmurings.

"I took Atchison for lunch over a year ago and told him, out of respect, of my intentions," Norris said in April. "We had a really frank, friendly conversation."

Dale Richardson, Norris's campaign manager, said Atchison's decision to enter the race is "a pretty interesting choice for a guy that's polling at roughly nine, 10 per cent, according to the numbers that we have."

Richardson was referring to custom polling Norris's campaign commissioned from Insightrix, the results of which he did not share.

"With respect to him, Saskatoon seems to have moved on from Mr. Atchison," Richardson said. "That was pretty clear in 2016 when over 60 per cent of people in Saskatoon didn't vote for him."

Asked if Norris's campaign worries Atchison could deter votes away from Norris and give Clark an edge, Richardson replied, "Rob's been out for two months so far. He's been doorknocking every day. In my experience, when I've gone out with him, there are very few, if any, people that are saying, 'You know, we'd like to go back to the days of Don Atchison.'"

Richardson added that people have been complimentary to Atchison.

"People say he did great things for the city. Lots of good things to point to," Richardson said.

Norris, who launched his campaign at the end of June, has his own announcement planned for Friday at 11:15 a.m., across the street from the Frances Morrison Central Library.

Norris held a media event the day Clark announced his reelection campaign.

Read Atchison's press release below. Don't see it? Click here.