Arizona’s Adrian Peterson eludes Tampa Bay’s Vernon Hargreaves. (Ralph Freso/Associated Pres)

It turns out that the best description for Adrian Peterson wasn’t “over the hill” so much as “underused.” The 32-year-old running back, who had trouble getting off the bench for the Saints before being traded to the Cardinals, turned in a vintage performance Sunday in his Arizona debut.

After trampling the Buccaneers for 134 yards and two touchdowns on 26 carries in a 38-33 Cards win, Peterson said, “That’s the opportunity I’ve been waiting for.” Indeed, following an injury-shortened 2016 season, he’s been waiting almost two years to submit such a dominant outing.

It couldn’t come soon enough for the Cardinals, who came into the game last in the NFL in rushing yards (259), yards per game (51.8) and yards per carry (2.59). In the wake of David Johnson’s Week 1 wrist injury, Arizona’s primary ball carrier had been Chris Johnson, who looked every bit of his 32 years and who was released following Peterson’s acquisition from New Orleans for a conditional draft pick.

“Once I got that call on Tuesday, I was rejuvenated,” Peterson told reporters (via azcardinals.com). “My wife even said, ‘It’s like a boulder was lifted off your back.’ ”

Released by the Vikings in the offseason after spending his first 10 seasons in Minnesota, Peterson signed with the Saints in April and expected to vie for work with incumbent Mark Ingram. Days later, however, New Orleans traded up in the draft for Alvin Kamara, and as soon as the season began, it became painfully evident, to Peterson and everyone else, that the 2012 NFL MVP was the odd man out.

In four games with the Saints, Peterson had 27 carries for 81 yards and zero touchdowns, adding two receptions for four yards. By the end of his first drive with the Cardinals, he had 54 yards and a score on just four carries, and Arizona had a new weapon that could force defenses to shift their focus away from stopping what had been a one-dimensional, pass-heavy attack.

“There was such a high percentage of eight-man boxes because he was in there,” said quarterback Carson Palmer, who completed 18 of 22 passes for 283 yards, three touchdowns and one interception. “The secondary and the underneath coverage is so affected by the possibility of the ball being in his hands.”

One Cardinal particularly happy to see Peterson play so well was Larry Fitzgerald, a Minneapolis native who is hosting his new teammate in his guesthouse. Fitzgerald, 34, caught 10 passes for 138 yards and a touchdown from Palmer, 37, while Peterson showed he had plenty left in the tank.

“Obviously,” Cardinals Coach Bruce Arians said, “a day for old guys.”

It remains to be seen whether Peterson can keep this up, but Arizona might only need the seven-time Pro Bowler to provide blasts from the past until Thanksgiving, when Johnson could be back. In the meantime, a move that smacked of desperation to some observers now appears to have been a stroke of brilliance, not to mention a godsend for a veteran player who just wanted a legitimate opportunity to prove himself.

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