REGINA - It's only Week 2 of the CFL season and the Saskatchewan Roughriders are already having to juggle their roster.

Kevin Glenn will start at quarterback with Darian Durant out for the season while placekicker Chris Milo has been placed on the inactive list for this week and could be out for longer. Linebacker Shea Emry is doubtful for Sunday's game against the Toronto Argonauts, as is rookie receiver Nick Demski.

Tino Sunseri rejoined the Roughriders after they cut him during training camp, while B.C. Lions castoff Paul McCallum has returned to Saskatchewan. All-star safety Tyron Brackenridge and speedy slotback Weston Dressler also return to the lineup this week.

But what gets lost in the plethora of transactions is the poor performance turned in by Saskatchewan's defence during its season-opening loss at home to the Winnipeg Blue Bombers.

"It looked like a Week 1 effort," said defensive end John Chick. "I don't want to sound too negative, but we know we have a lot more that we can improve on."

The Riders allowed 167 combined yards to Winnipeg tailback Paris Cotton and 470 total yards of offence to Drew Willy's club. Willy carved up the secondary for 325 yards passing and three touchdowns, while only being sacked once. The Saskatchewan defence also failed to create any turnovers.

"He's a good runner," said Brackenridge of Cotton. "But it starts with us. We have to focus and take it more seriously. We have to get back to fundamentals … getting our eyes in the proper place and making it happen."

Saskatchewan's defence is young but the Riders aren't using lack of experience as an excuse.

"No matter who is in there playing, if they're not getting the job done then that's on all of us," Chick said. "That's our job and our responsibility. The next guy up is all of a sudden a starter and he's got a job to do."

"We have a lot of potential with this group," he added. "But it's a matter of reaching that potential. You're always trying to improve, and this past game was more of a letdown on fundamentals than scheme or anything like that."

Durant, who suffered a season-ending elbow injury in Week 11 of the 2014 season, ruptured the Achilles tendon in his left foot against Winnipeg. The injury happened late in the second quarter when he landed awkwardly after a pass attempt.

Emry, meanwhile, has a neck injury while Milo's days in Saskatchewan appear to be numbered. Roughriders coach Corey Chamblin said the 45-year-old McCallum, who was cut by the Lions in training camp, will handle the converts and field goal attempts this week.

Ray Early will do the punting and the long field goals.

Milo converted on one of two field goal attempts in Week 1. He made a 19-yard attempt, but missed from 35 yards out.

"We need more consistency in that area," Chamblin said.

The Riders will have their hands full against an explosive Argos offence that looked strong in a 26-11 win over the Edmonton Eskimos last week. Brandon Whitaker rushed for a game-high 117 yards on 14 carries and receiver Chad Owens had seven catches for 99 yards.

Owens added 60 yards on punt returns. Quarterback Trevor Harris torched Edmonton for 347 yards passing and three touchdowns.

"If we want to achieve what we talked about at the start of the year then we're going to have to get that started this weekend against Toronto," Chick said. "We need to get a win at home."