Safety Tyrann Mathieu is trying to return from a knee injury, but his availability in the opener is in doubt.

It could be said that safety Tyrann Mathieu passed another hurdle in his knee recovery on Thursday. The Cardinals put on pads for live hitting, and for the first time he entered the fray completely, listed as a full participant.

After practice, though, a low-key Mathieu didn't make a big deal of the progress and is unsure of his status for Monday

night's season opener against the Chargers.

"I think about two weeks ago I stopped looking that far," Mathieu said. "I just kind of want to handle the day, get through the day, and then focus on the next day. So I don't know."

Coach Bruce Arians said Mathieu made three or four tackles against wide receivers and tight ends but also missed three. When asked if that was encouraging, Arians said, "It's good he got three. I'd have been really (ticked off) if he got 0-fer."

Mathieu said it will be up to the trainers and coaching staff to decide when he plays, and for now his goal is to get back up to speed in practice.

"The more reps I get, the more comfortable I get," Mathieu said. "I see things before it happens, but it's all about becoming more comfortable and doing it."

Arians said last week that any player who missed the preseason finale against San Diego would not play in the opener. He seems open to back-tracking on that statement if Mathieu is ready, but at this point it seems Mathieu's mind is still waiting for his body to catch up.

"I know my plays and I know where I'm supposed to be at," Mathieu said. "It's just a matter of me getting to 100 percent."

GINN READY TO MAKE IMPACT IN RETURN GAME

The Cardinals received minimal production from their return game in 2013, as they were 31st in both kickoff return average (20.0) and punt return average (5.8). Wide receiver Ted Ginn enters the fold this season after averaging 23.8 and 12.2 yards in those respective roles and is expected to help the unit.

"Hopefully we should be very explosive," Arians said. "I think the guys all know it's the blocking for him. He just needs a crack. When you have a guy back there with his pedigree, it helps when you're blocking for a guy like that."

Cornerback Patrick Peterson handled punt return duties last season, but teams were sometimes wary of punting deep and giving him lanes to run. Ginn said he will have to remain patient if punters use the same tactics against him.

"It's hard to return every last one of them, but the ones you get, you make the best of them," Ginn said. "You might have three or four fair catches, and that one that you don't might take it to the house. You never know."

Ginn said it's great to get a big return, but it's also important to weigh the risk of returning a kick, especially now with kickoffs five yards closer to the end zone.

"Your main goal is to get past the 20 or better," he said. "If you think you can't get there, you just take a knee and your team goes 80 yards. It's very seldom that teams go 90 every time."

DEFENSE GETS ITS FIRST SHOT AGAINST SAN DIEGO

Chargers quarterback Philip Rivers led the NFL in completion percentage last year and the team's offense helped carry it to a playoff berth. Most of the key pieces return, as running back Ryan Mathews, tight end Antonio Gates and wide receiver Keenan Allen are a few of the skill pieces the Cardinals must slow down.

It will be the first look at the revamped defense, which will be without standouts Karlos Dansby, Daryl Washington and Darnell Dockett from a year ago. The preseason results were encouraging, but the San Diego game will be a much better litmus test.

Between the season opener and Monday Night Football, the crowd is expected to be electric, which Arians said the team will use to its advantage.

"They've got multiple weapons and they're very good," Arians said. "It'll be a great test, and hopefully the crowd noise will help us. We'll feed off the energy of the crowd."

MOSTLY HEALTHY HEADING INTO THE SEASON

Linebacker Alex Okafor missed practice with a thigh injury, while running back Andre Ellington (foot) was listed as a limited participant on the injury report.

Guard Jonathan Cooper (toe), wide receiver Larry Fitzgerald (knee), linebacker Kevin Minter (chest) and defensive tackle Frostee Rucker (back) joined Mathieu as full participants in practice.