It’s too early to say the 49ers have a Cybil-like crisis on their hands, but two different teams have made an appearance to this point.

When the 49ers face the unbeaten Cardinals in Arizona today, coach Jim Tomsula figures to get a better handle on his team.

“I haven’t tried to fool anybody,” Tomsula said. “We have a lot of work to do, but we’ve got guys that are willing to work and we’re working.”

In their first NFC West test, the 49ers may want to start with a heavy does of Carlos Hyde on offense. He set the tone against the Minnesota Vikings in the regular-season opener, and the rest fell into place in a 20-3 victory.

Last week, Hyde was limited to 43 rushing yards in a 43-18 loss to the Pittsburgh Steelers before he left the game with a concussion and bruised quadriceps in the second half. He is expected to start today and run with his familiar abandon.

“I just don’t think you change a man’s DNA that way,” Tomsula said. “That’s him. That’s what he does. That’s what we love about him.”

Tomsula prefers to rotate backs, and the return of Reggie Bush will allow him to do it — though when that will happen remains an issue. The veteran strained his left calf early in the first game, and his status was doubtful Friday.

When healthy, the 30-year-old Bush can be a valuable contributor to the offense. He is particularly adept on screen and swing passes, which are an extension of the run game. The longer the offense controls the ball, the less a revamped defense that was gashed for 453 yards in only 23 minutes last weekend is required to be on the field.

In his first season as defense coordinator, Eric Mangini conceded a new system with so many new pieces has been a difficult challenge for the group.

“Yeah, there really is a growth that goes into any defense, because I’m learning about the guys, the coaches are learning about the guys, they are learning about us,” Mangini said. “We’re figuring out as we go, things we do really well, things we don’t do as well.”

Last weekend Mangini tried to mask defenses in an attempt to confuse Steelers’ quarterback Ben Roethlisberger, but he seemed only to outsmart his players. On several occasions, defenders were out of position in the secondary, and the result was six plays of 28 yards or more. The longest of the Steelers’ six touchdowns took all of eight plays.

A feeble pass rush didn’t help matters, either. The defense failed to record a sack in 27 drop-backs.

Rather than make changes at this early stage, Tomsula prefers to err on the side of stability. He has no line-up changes planned at this time.

“Do I have faith in [the defense]? Yeah,” Tomsula said. “Am I excited about the guys we have? Absolutely. Do we have to continue to get better day to day, week to week? Yes.”

The secondary will have its hands full for the second consecutive week. Wide receiver Larry Fitzgerald and quarterback Carson Palmer have played some of their best ball lately, and in burner John Brown, the Cardinals have a longball threat.

“You know, it’s such a copycat league,” Mangini said. “It’s like anything else, whoever you get hit on something, they’re going to try to hit you again, and the next team will and team after that will. And you do the same thing defensively. If you see something that you think could be problematic, you say, ‘OK, is it fixed?’ And until you go out and show that’s it’s fixed. they’ll keep pressing.”

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