The team announced on Saturday it had ended Tillman's contract effective immediately and Eskimos president and CEO Len Rhodes said in a statement that he "did not see Eric as a part of this team moving forward."
But Rhodes declined to give a reason for the decision at a media conference and insisted over and over that there was no single cause for Tillman's dismissal.
"It's what I believe is in the best interests of the club, for the long term of the club," said Rhodes. "I'm very proud of what Eric's done. Everything he's done has been what he thought was in the best interests of the club. It's a business decision.
"We've decided to go with someone else."
The timing, however, is surprising as Edmonton (7-11) finished its regular season Friday with a third straight loss, 30-27 to the Calgary Stampeders but still qualified for the post-season.
The Eskimos will face the Toronto Argonauts in the East Division semifinal Nov. 11 at Rogers Centre after earning a cross-over berth.
Rhodes said he informed the team's board on Oct. 25 that he wanted to replace Tillman and he said he had the board's full support. He said Tillman was informed after returning to Edmonton on Friday and that he took the news "like a gentleman."
There had been much speculation of friction between the 55-year-old Tillman and other members of Edmonton's front office. Also, Tillman hadn't moved his family to Alberta from Regina since joining the Esks, which raised questions about his commitment to the CFL club.
Another alleged sticking point between the club and Tillman was the trade of former Eskimos quarterback Ricky Ray — who will lead the Argonauts on Nov. 11 — for QB Steven Jyles, kicker Grant Shaw and the second pick of the 2012 CFL draft last December.
Ray led Edmonton to two Grey Cup titles over his nine seasons there.
Tillman came under a lot of fire for the move of Ray, who not only was one of the most prolific passers in franchise history but also a huge fan favourite.
Rhodes, however, dismissed the idea that Tillman's dismissal had anything to do with the Ray trade.
"At the time, I approved of the trade. Why would I relieve someone when I approved of the trade to begin with?" Rhodes asked.
Ray guided the Eskimos to an 11-7 record last year and a tie for first in the West Division with B.C. and Calgary. Edmonton dispatched the Stampeders 33-19 in the opening playoff round before losing to the eventual Grey Cup-champion Lions 40-23 in the conference final.
The Eskimos were 2-0 against Ray and the Argos this season, but Toronto (9-9) not only posted a better record than Edmonton but Ray threw for 4,059 yards this year, the seventh time in his CFL career he has surpassed the 4,000-yard passing plateau. Ray missed three regular-season games with a knee injury but in his two starts since returning has thrown for eight TDs and given up just one interception.
Ray didn't dress for Toronto's regular-season finale, a 43-40 home win over Hamilton on Thursday night, which ironically clinched the Eskimos a playoff berth.
Rhodes also said that while the club would have preferred Tillman had moved to Edmonton, he wouldn't single it out as a factor in the decision to replace him.
He said rather than being a distraction heading into the playoffs, he said he hoped it would focus the team.
"Our head coach and his coaching staff and the players have to be focused on what's going on going into Toronto," said Rhodes. "We started the season with the objective of getting into the playoffs. We're in the playoffs. Now there's a reset button.
"Everyone's on the same page. We're going to give it our best shot."
Tillman is a veteran CFL executive, having served as GM previously with B.C. ('93-'94), Toronto (1997, '99), Ottawa (2002-'04) and Saskatchewan (2006-'10). His teams have made four Grey Cup appearances, winning three times (1994, '97 and '07).
Tillman began his CFL career in 1982 as the player-personnel director of the Montreal Concordes before serving as the executive director of the Senior Bowl in Mobile, Ala., from 1984 to 1993.
There was much speculation this season that Tillman could be returning to Toronto despite present Argos GM Jim Barker still having one year remaining on his deal. Tillman's name has also been mentioned as a potential GM of the new Ottawa expansion franchise.
Edmonton has struggled offensively this season, using three quarterbacks — veterans Jyles and Kerry Joseph and youngster Matt Nichols. The Eskimos entered the final week of the regular season last overall in offensive yards (333 per game) and second-last in scoring (23.2 yards per game). Earlier this season, head coach Kavis Reed took over the offensive co-ordinator's duties from Marcus Crandell, who was named quarterback coach.
Tillman was hired as Eskimos GM on Sept. 14, 2010, taking over a team that had a league-worst 2-8 record. Edmonton finished the season winning five of its eight remaining games but ended up just two points out of the final West Division playoff spot.
Rhodes said the team hopes to hire a replacement by the start of next year.
Tillman was charged with sexual assault Jan. 27, 2009 in an incident involving a 16-year-old girl in Regina. Tillman pleaded guilty to the charge Jan. 4, 2010 and was granted an absolute discharge the following day. As a result, he received no criminal record but Tillman resigned as Riders GM on Jan. 8, 2010.