According to head coach Ken Wisenhunt and Leinart himself, the fifth-year quarterback out of USC is taking the necessary steps both on and off the field to be the main man behind center this fall.
Now that Kurt Warner has hung up his cleats, now is the perfect time for Leinart to show he can lead the Cardinals, who have suddenly become the toast of the NFC West.
Speaking on XTRA 910 radio in Phoenix, Leinart said he has matured over the past few seasons and now has a better grasp of the offensive playbook and its game plan.
"This is the first time in a long time where I feel confident every single day," Leinart told the station. "I know that I know what I am doing."
Leinart also noted that he has been changed by the birth of his son. This probably means no more beer bongs or wild hot tub parties.
"Obviously I have had some ups and downs, but just what I learned and have been through the last three or four years is such a big difference," Leinart quipped to XTRA 910. "I think no matter what you do in life from twenty-one to twenty-seven you are just going to mature.
"That is human nature, but for me just having to deal with what I have dealt with and then being a father, which is the greatest blessing of all-time... I have always been focused on football, to be honest with you, I have always loved it."
Even Wisenhunt, who was unimpressed with Leinart's off-the-field antics, recently said Leinart has looked sharper and more consistent in the team's Organized Team Activities.
While this piece of news should give Cardinals fans reason for hope this fall, they also must remember that the calendar just hit June. The games that count don't start until the Cards open the season September 12 in St. Louis.
Leinart can say all of the right things now and could look confident on the practice field, but until he proves he can take over for Warner, he hasn't done enough.
And while he doesn't have to be as spectacular as Warner was (especially with an emerging running game), all Cardinals fans care about winning.