Fiery Scot Ferguson was dismissed ten minutes from time - just seven minutes after coming off the bench - when he appeared to punch Wigan's Paul Scharner after a flare-up.
Then Roberts was shown the red card with ref Mike Dean ruling that he had elbowed Everton defender David Weir.
David Thompson, a goalscoring hero on his Wigan debut at Middlesbrough,had earlier found himself cast as the villain on his home debut, putting through his own goal to give Everton an early lead.
But a spectacular effort from man-of-the-match Scharner earned Wigan a deserved share of the points while Everton continued their unbeaten start to the year.
Everton were boasting seven games without a defeat - including four successive wins in the Premiership.
The Toffees were boosted by the return of goalscoring midfielder Tim Cahill and experienced defender Alan Stubbs who missed the FA Cup draw against Chelsea.
James McFadden who picked up a shin injury and a broken nose in the Chelsea game was cleared to play but £6million striker James Beattie was not risked by David Moyes.
Wigan - closing in on Paul Jewell's 40-point survival target - had Roberts, Jimmy Bullard and Thompson back in the starting line-up, and skipper Arjan De Zeeuw returned after a three-match injury absence.
Everton struck first opening the scoring after nine minutes following slack marking at the back by the Latics.
Persistence by Cahill on the edge of the box earned him the right to shoot and he got a fortunate deflection off Stepane Henchoz.
Thompson and Leon Osman both competed for it and while Osman claimed it, it was the Latics player who got the vital touch.
Wigan were making little headway - De Zeeuw providing the first test for Richard Wright from a Leighton Baines free-kick. But the header failed to trouble the Everton keeper.
Everton threatened again when a neat touch from Osman sent McFadden in on goal. Mike Pollitt could not hold the shot and was lucky not to be punished as Cahill almost cashed in on the slip.
A typical Gary Teale raid down the right produced a chance for Scharner who made a lot of ground to get into the box but headed over.
Twice skipper De Zeeuw suffered similar misfortune failing to find the target with headers.
But the Latics levelled it with a terrific finish on the stroke of half-time after Roberts had had one ruled out for offside.
Everton cleared a Thompson free-kick but only as far as Henchoz. He pumped it forward to Pascal Chimbonda and the right-back turned the header inside for Austrian star Scharner to volley in the equaliser from the edge of the six-yard area.
Then in stoppage time, Wright came to Everton's rescue keeping out Roberts, who again threatened straight from the re-start.
But it took an excellent stop from Pollitt to deny Everton when the unmarked Mikel Arteta looked a certain scorer.
Wigan had a penalty shout turned down when David Weir appeared to impede Roberts but from the corner, De Zeeuw's header whistled just over the bar.
The ever dangerous Roberts had the ball in the Everton net again but ref Dean ruled it out for a push on Stubbs.
Aussie Cahill was a whisker away at the other end as both teams attempted to conjure up a winner.
But the match exploded in the last 12 minutes with both sides reduced to ten men.