Cardinals wide receiver Larry Fitzgerald had a big day as the offense rolled on Sunday.

The Cardinals wore black on Sunday, and another lackluster loss may have resulted in their funeral.

Instead, Adrian Peterson brought vitality, not only to the offense but to an entire legion of frustrated fans.

The Cardinals were lucky to be 2-3 heading into their game against the Buccaneers, capturing uninspiring wins over the lowly 49ers and Colts. They finally looked like a legitimate playoff contender against Tampa Bay, jumping out to a 31-0 third-quarter lead and holding on for the 38-33 victory.

Despite the late nail biting, the Cardinals dominated over a long stretch for the first time this season. After so much success in recent years, the players were anxiously waiting for a performance to harken back to those days.

"I feel like this is a game where we showed everyone that this is what we're about," money linebacker Deone Bucannon said.

The offense was abysmal through the first five games, and while adding running back Adrian Peterson sounded good in theory, there was a chance it worked better on paper than in reality.

That notion was extinguished on the first series, when Peterson looked like an unleashed bull in Pamplona, flying through running lanes with reckless abandon.

Peterson never slowed down, finishing with 26 carries for 134 yards and two touchdowns. Several teammates with first-round pedigrees of their own gushed about the performance. Outside linebacker Chandler Jones was in awe seeing a player he used to watch in high school.

"He got on his knees (after scoring), just like he used to do in Madden," Jones said.

Left tackle D.J. Humphries sounded like a conspiracy theorist in the postgame locker room.

"I told him during the game, 'There's no way that you're 32, bro,'" Humphries said. "'Like, I don't believe that. I think you're my age. The way you're running this ball, you've got to be 23. I don't care what you're talking about. I don't care what your birth certificate says.' I think he got in the league way earlier than he was supposed to, and he tried to play it off like he was really old. But it's coming to light now. That don't make sense. There's no way he's 32."

A week ago, the Cardinals continued a troubling season-long trend of offensive ineptitude and defensive letdowns in a blowout loss to the Eagles. There were issues on Sunday as the Bucs rallied late, but the Cardinals finally looked like a team with upside.

The quarterback pressure was consistent and the secondary picked off a pair of passes. The offense isn't going to rack up 432 yards of offense and go more than 40 minutes without punting on a regular basis, but the ceiling, it seems, has been raised.

"The talent level on this offense is absurd," Humphries said. "It's just about putting it all together like we did today."

Peterson has changed the game, giving an offense lacking in playmakers an immediate boost.

"I can guarantee the Rams weren't anticipating this two weeks ago," quarterback Carson Palmer said. "It's a big lift. Everybody in here, I'm sure, felt the intensity that our crowd brought today and the excitement in the air."

It was a level of enthusiasm that had been missing for all of 2017. Suddenly, the NFC West looks like a three-team race. The Cardinals started slowly, but after Sunday, they can argue those five games were an early sputter and not indicative of a team with fatal flaws.

"We have a lot to work on, but it was good to see our potential," safety Tyrann Mathieu said.

The Cardinals hope a trip to London for a showdown with the division-leading Rams next week won't halt the momentum.

"When you get hot – and you want to get hot at the right time – you've got to ride that," cornerback Tramon Williams said. "You've got to ride that wave."