Tlusty also had an assist on the game winner.
He looked solid in goal, stopping 27 shots.
Daniel Larsson started in net for the Griffins and made 30 saves.
Deveaux received a pass from Tlusty deep in the Griffins zone and beat Larsson for the winner.
Marlies coach Dallas Eakins told reporters after the game the hero of the moment wasn’t supposed to be on the ice at that point.
“I was waiting for Deveaux to come off the ice so Hanson could go out,” Eakins said. “But Deveaux had a little bit left in the tank and that was his call.”
For dramatic effect, each period ended with a goal in the final minute.
With Grand Rapids leading 2-0 in the second period, former Marlie Kris Newbury was penalized for roughing at 11:19.
Toronto quickly capitalized nine seconds into the powerplay when Tlusty deked to his backhand and slipped the puck past a sprawling Larsson to trim the Griffins’ lead to 2-1.
The Marlies finished 1-for-7 on the powerplay, while the Griffins went scoreless on four chances.
Mikus scored on a wrist shot from the right faceoff circle with 19 seconds remaining in the frame to knot the game at two through 40 minutes.
“It was nice to be even heading into the third,” Eakins said. “When those late goals are against you, they hurt you, but when you get them, they can be real positive for your group so that was huge for us.”
Through the first 10 minutes of the opening frame, the Marlies held a 9-2 lead in shots. Grand Rapids picked up the pace, outshooting Toronto 6-2 over the final half of the period.
Williams made his former squad pay for a turnover in its own zone by scoring uncontested off a wrist shot at 13:35 of the first.
He is the Marlies’ all-time leader in goals with 74 and added his first as a Griffin.
The Marlies looked to leave the period without any further damage, but Grand Rapids had other plans.
Janik was left wide open at the point and his slapshot beat James Reimer with a tick remaining on the scoreboard.
After that goal, Eakins had a message for his team.
“I told them we could either feel bad about ourselves and have negative thoughts, or kick that period out of the window and start thinking positive things,” he said.
“When you don’t play for a full week, it’s tough to get going sometimes and I just thought we got better as the game went on.”
This season, Eakins is placing special emphasis on fitness and has his players on the exercise bikes after games.
“It’s mandatory,” he said. “There’s a different workout depending on the amount of minutes you played. If it’s a lot of minutes, it’ll be a little less work and a little more recovery.”
Reimer will get the start in tomorrow’s game against the Rockford IceHogs.
Notes: Andy Rogers, Phil Oreskovic, Todd Perry, Darryl Boyce, and Robert Slaney did not dress for the Marlies … Tlusty has 15 points in his last eight games against the Griffins … Newbury and Williams were picked up by the Detorit Red Wings in July and assigned to the Griffins. They are first and second respectively in all-time Marlies points with 168 and 144.