The former Notre Dame star returns under centre Monday when Toronto hosts the Saskatchewan Roughriders in a crucial contest for both teams. Jackson will make a second straight start with incumbent Ricky Ray (knee) still out.
Joining Jackson in the backfield will be rookie Gerald Riggs Jr., who'll replace injured starter Chad Kackert (ribs).
Jackson, 35, led Toronto to a 29-10 road win in Winnipeg on Sept. 29, his first CFL start since Aug. 12, 2010. After seeing no reps with the starting offence when Ray was healthy, Jackson has benefited having two full weeks to work with the unit.
''Big time, just the constant repetition of seeing the plays," Jackson said. "You get down the pace of the guys getting to the line of scrimmage, the O-line making its calls.
"There are so many variables that go into it and when you're actually in there you can get into the flow and into the groove to where everybody can be on the same page.''
Jackson showed the poise of an eight-year veteran against Winnipeg, completing 17-of-28 passes for 155 yards and a TD. He effectively managed a Toronto offence that held the ball for over 37 minutes against the Bombers.
"Jarious has been pretty consistent," Argos head coach Scott Milanovich said. "I do see a little bit more confidence (in practice) . . . he's just more comfortable and that comes with the reps.''
Jackson's mobility also provides an added element for Toronto's offence as he ran seven times for 51 yards and a TD against Winnipeg.
"When you devise schemes to stop five receivers and a running back, the quarterback is hardly accounted for," Jackson said. "If you come up with schemes and have linebackers and other guys going to help receivers, the threat of a quarterback running gives defensive co-ordinators nightmares.''
If there's a knock on Jackson, though, he doesn't always slide when scrambling. And with untested rookie Trevor Harris now the Argos' backup, the club can't afford to lose him to injury.
"I'm going to be smart about it," Jackson said. "If I have to fight for the first down and help my team win, then I'm going to go head-first.
"If I've got three guys bearing down on me and it's a wide-open field then I'm going to slide. I'm not going to be crazy with the situation.''
Riders head coach Corey Chamblin has plenty of respect for Jackson's mobility and experience.
"The biggest thing with Jarious is you expect him to be poised," Chamblin said. "He understands we're going to try to hit him, he knows me very well and knows we're going to come after him but he'll stand in there and will run around and throw the deep ball when he needs to.
"I think it's a test for our defence because we're playing Jarious and there's not a lot of film on him and we don't know how much they can do whereas their defence knows what we can do (with veteran starter Darian Durant) and (Argos defensive co-ordinator) Chris Jones will have them ready."
A fact not lost upon Riders' linebacker Tyron Brackenridge
"I see a guy who has a lot of confidence, a guy who can come in and make plays with his feet and makes good choices with his receivers," he said. "We have to play sound football.
"We have to play our assignments and do what the coaches put us in position to do and play fast. Playing fast and physical is the key for us and that has given us a lot of success.''
The game is an important one for both teams.
Toronto (7-6) is second in the East Division, two points behind first-place Montreal (8-5), which faces Winnipeg (3-10) also Monday. The Argos host the Alouettes next weekend and at worst must still be within two points entering that contest to still realistically have a shot at top spot and hosting the conference final Nov. 18.
Saskatchewan (7-6) is third in the West Division, two points behind Calgary (8-6) but also just two points ahead of Edmonton (6-8). The Riders are also still in the crossover hunt as in the CFL if a fourth-place team posts a better record than the third-place squad in the opposing division, the fourth-place club assumes the final playoff spot in that conference.
Currently, Hamilton (5-9) is third in the East Division.
"It's a playoff game," Jackson said. "It's the last third of the season, you're talking about jockeying for a position and wanting home-field advantage. This is the time to turn it up, there is no waiting.
"We're a 7-6 team right now, we're just barely .500. We have no room to slack off or not take any game seriously.''
Saskatchewan's defence will present a formidable challenge for Jackson and Co. The unit is allowing just 21.5 points per game (second-lowest in CFL) and has 27 sacks — 10 more than Toronto.
Offensively, the Riders also have plenty of threats with Durant (2,927 yards passing), running back Kory Sheets (922 yards, eight TDs) and slotback Weston Dressler (77 catches, 1,000 yards, nine TDs).
"We're playing a team that has a lot of weapons offensively and so what we have to do is be relatively efficient offensively," Milanovich said. "It's not a game where we have to go and think we have to score 50 points but we can't be two-and-out all night long and keep giving Durant and his guys chances to wear our defence down.
"For us we have to move the ball, control the clock, play field position, get points when we get the chance to. We'll have chances to make big plays, there are in every single game. We have to make more than they do. This time of the year it ultimately comes down to turnovers. We're home, we have to protect the football, we have to get after their quarterback.''