GLENDALE, Ariz. (AP) -- After going 10-6 and barely missing the playoffs, the Arizona Cardinals are a confident but wary bunch as they open their second training camp under coach Bruce Arians.
''You can sense the energy'' among the players, said defensive tackle Darnell Dockett. ''These guys, they know the sacrifices we're going to have to make. It's not going to be easy. It ain't just show up and try to get by.''
Arians had the same observation.
''It's more confidence than optimism,'' he said. ''They know how tough it will be, but they have all the confidence in the world they will get it done.''
The players went through conditioning tests Friday in the air conditioned comfort of University of Phoenix Stadium while temperatures outside reached 108 degrees.
Arians, who seems to genuinely enjoy dealing with the media, joked he couldn't decide which reporter to make run the test, too.
The players, he said, were in excellent condition.
Arians even joked that big nose tackle Dan Williams, who has had weight issues in the past, ''looked as sexy in the run test as he's ever looked.''.
While the elements are there for a playoff run, several questions remain.
First and foremost is the competition - the NFC West is loaded with Super Bowl champion Seattle, powerful San Francisco and much-improved St. Louis.
Running back Andre Ellington welcomed the challenge.
''We thrive on them,'' he said.
The team's dynamic inside linebackers of a year ago - Daryl Washington and Karlos Dansby - are gone. There is competition at right guard, right tackle, tight end and strong safety.
Free safety Tyrann Mathieu probably will miss the first few games of the regular season recovering from knee surgery. He estimated that he will be sidelined for 6 to 8 weeks.
That would put him back for the Monday night opener Sept. 8 against San Diego at the earliest, and he'd miss two games at most. Of course, it could be longer.
Mathieu and nose tackle Alameda Ta'amu opened camp on the physically unable to perform list. Both ran the drill on Friday.
''It's a matter of getting them in football shape,'' Arians said. ''and not pushing them too fast. They're too good of young players to push too fast.''
A year ago, Arians was immersed in teaching his system to the players. This year, they know it well.
''It's so much easier. The daily process just runs easy now. It's' night and day,'' he said. ''That first year is always tough. I really like the way our team battled through the second half of the season. It makes this one more important and easier to get started. We have a good taste in our mouth but we're not satisfied.''
The players seemed eager to get started.
''It's like you can't wait for Christmas Day,'' Ellington said. ''Everybody wants to get this thing going.''
Ellington, an electrifying, fast runner, is to get an expanded role as the lead running back, and beefed up only slightly, he embraces that role.
''I'm excited for it but it's a lot of work I've got to do out on the practice field,'' he said, ''just to show him and all of the staff that I'm ready to go.''
Outside linebacker John Abraham was excused Friday for personal reasons, Arians said.
Fans will be allowed at the workouts starting Saturday.
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