The 2015 Firestone Grand Prix of St. Petersburg may one day be remembered as the race that started the resurgence of Juan Pablo Montoya.

The one-time open wheel phenom from Colombia drove to an impressive victory Sunday, beating Team Penske teammate Will Power by about a second before what could have been the largest crowd in Grand Prix history.

Montoya was dazzling way back in 1999, when the won the championship of the old CART series as a rookie and then in 2000, when he blew to victory the Indy 500. That helped earn him six seasons in Formula One and eight in NASCAR before he joined the IndyCar series last year.

He won a race and finished fourth in the standings last year, but Sunday, he really looked like the old Montoya.

"Juan was always going to be Juan," said Sunday's third-place finisher, Tony Kanaan. "He's good. I mean, I don't understand whoever thought he wasn't. Obviously, it took him a year to get a grip on things, and he's back."

It didn't hurt that he was with the best team. Penske swept the top four spots in qualifying Saturday and won the race for the seventh time 11 years. The other two Penske drivers, Helio Castroneves and Simon Pagenaud, finished fourth and fifth.

St. Pete was Montoya's first race back last year, and unaccustomed to the car, he qualified 18th and finished 15th. He didn't win a road or street course race all year (his victory came on the oval at Pocono).

"I'll tell you the big difference between myself this year and last year," Montoya said. "Last year, going on the restarts, I was thinking, 'Don't hit anything. ... In these restarts, I knew how far I could brake and make the corner, you know what I mean? Everything just clicked."

Montoya's biggest challenge Sunday was holding back Power, the defending IndyCar champion and last year's St. Pete winner. But he got passed Power during green flag pit stops and shut him down in his one attempt to get back to the front. Power did manage to lead 75 of the 110 laps.

St. Petersburg’s Sebastien Bourdais finished sixth, 2014 Indy 500 winner Ryan Hunter-Reay seventh and Jack Hacksworth eighth. The only woman in the field, Simona de Silvestro, had a series of misadventures and wound up 18th.

The race also marked the debut of IndyCar's new "aero kits" — bodywork that gives the cars a fresh look — and there were numerous parts and pieces breaking off the cars during the race. Three of the five caution flags were for debris.

"The new aero kits made the racing a lot closer, which I couldn't believe was going to happen," Kanaan said. "Of course, when you add more flaps and more wings, the chances to see more pieces flying are greater."

Grand Prix officials don't give attendance figures, but promoter Kevin Savoree said the weekend was "huge." With perfect weather Sunday, the crowd appeared to be at least as big as any previous Grand Prix.

Tampa Bay Buccaneers wide receiver Vincent Jackson was the grand marshal and gave an enthusiastic, if gruff, command for drivers to start their engines. Before that, he stopped at the Team Penske workspace in the paddock and traded Castroneves a Bucs jersey for a Size XXL Hitachi Team Penske shirt.

He then presented Savoree and his partner, Kim Green, with jerseys with their names on the back.