LONDON (AP) -- Matt Cassel will get a chance to steer the Minnesota Vikings to their first win of the season - and maybe put himself in position for a more regular role.
Cassel will replace injured starter Christian Ponder at quarterback against the Pittsburgh Steelers on Sunday at Wembley Stadium. The Vikings (0-3) ruled out Ponder on Friday with a fractured rib sustained in last weekend's 31-27 loss to the Cleveland Browns.
''We worked with Matt in the mindset that this was a possibility, so I think we're prepared in that way,'' coach Leslie Frazier said. ''He's been in this role before. His veteran presence - you can feel it. So there was no shock this week as he got more and more reps. I think (the team) will handle it the right way.''
Cassel hasn't played a down this season since signing a two-year deal with the Vikings in the offseason. The former New England Patriot threw six touchdowns and 12 interceptions in nine games for the 2-14 Chiefs last season.
''I've been preparing for this and I feel like I'm ready to go,'' Cassel said. ''I feel comfortable with this offense. I'm excited about it. That's what you prepare for as a backup.''
Frazier is hoping Cassel will go out at Wembley and make a statement.
''I'm hoping that he shines, but I don't foresee a quarterback controversy,'' Frazier said. ''We want him to play lights out and have the best game of his NFL career on Sunday.''
If Cassel does shine, it could leave Frazier with a decision on who to start against the Carolina Panthers on Oct. 13 after the bye week.
Ponder, a third-year pro, has struggled this season, throwing two touchdowns and five interceptions for a 65.9 passer rating. He also has lost two fumbles.
Ponder had taken the majority of snaps in practice Thursday and looked determined to play Sunday.
''We just felt like it was, from a medical standpoint, too risky to put him out there to take a hit,'' Frazier said. ''He's a tough guy but it probably wouldn't be wise to put him out in that situation.''
''He's a competitive guy and he's played through some tough injuries here. He wanted to play,'' Frazier said. ''This is something you don't know how many times you'll get a chance to play in a game like this, but it's probably wise since we have a bye coming up, so he understands.''
Also ruled out for the Vikings are cornerback Chris Cook (groin), safety Jamarca Sanford (hamstring), and tight end Rhett Ellison (knee).
The rest of the players on the Vikings' injury report all practiced in full Friday and are probable for Sunday's game. They are running back Matt Asiata (hamstring), cornerback A.J. Jefferson (ankle), defensive tackle Kevin Williams (knee), linebacker Erin Henderson (heel), and long snapper Cullen Loeffler (neck).
The Vikings and Steelers are both 0-3 heading into the NFL International Series match at Wembley Stadium.
AP NFL website: http://www.pro32.ap.org