Matt Cassel should have returned from the Vikings’ bye week in a pretty good mood. He led the team to a 34-27 victory over Pittsburgh in London on Sept. 29, posting a 123.4 quarterback rating that was the team’s highest since Brett Favre’s 134.4 in a playoff game against Dallas following the 2010 season.

Instead, Cassel found out Monday morning that the Vikings were bringing in Josh Freeman to battle Christian Ponder and Cassel for the starting job. Cassel spoke to coach Leslie Frazier and General Manager Rick Spielman before the team’s practice.

“It wasn’t a tough conversation,” the nine-year veteran said. “One thing you can expect in the NFL — expect the unexpected. You never know what’s going to happen.

“They probably said the same thing they did to [the media], that they thought he was a quality player and that they want to create more competition at our position. I don’t look at it as a slight to myself. As long as I go out and continue to perform, everything will take care of itself.”

Cassel started in London, and is likely to start Sunday against Carolina, because Ponder has a fractured rib.

“I haven’t been told anything,” Cassel said. “We’ll go through a week of practice, see how everything goes, see how Christian is feeling and the decision will be made. Ultimately, none of us compete against each other. We’re going out there and whoever is playing, hopefully we support each other.”

Frazier said neither Ponder nor Cassel had any outward concerns when he met with them.

“They just wanted to know from me what the move entailed, and how it would affect them,” the Vikings coach said. “I think we’re all on the same page, how it affects them, and how it affects our team.”

Defending the defense

The Vikings are 30th in the NFL in total defense (430.8 yards allowed per game) and 29th against the pass (326.0).

Two of the team’s top defensive players were more concerned about those categories than they were about a quarterback controversy.

“We have enough stuff to worry about so we’re not going to try to let any of this become a distraction,” linebacker Chad Greenway said. “We’re 1-3 for a reason, a lot of things that we can clean up defensively. We need to focus on that.”

Cornerback Chris Cook (groin) and safety Jamarca Sanford (hamstring) went through a light practice Monday and seem likely to return Sunday after not playing in London, where Pittsburgh’s Ben Roethlisberger completed 36 passes and threw for 383 yards.

“We still have some things to shore up, especially in the secondary,” safety Harrison Smith said. “We’re doing some good things, but we can get better in a lot of areas.

“[Injuries] are part of the game, you obviously never want to see a guy go down … but it’s an opportunity for the next guy to step in.”