Castroneves won the Grand Prix of St Petersburg, Florida in the what was the first race since Wheldon was tragically killed in a horrific 15-car smash at the Las Vegas Motor Speedway in October.

After taking the chequered flag, the Brazilian driver stopped at turn 10 of the street circuit to pay tribute to his friend on a road named in honour of the British born, two-time Indy 500 winner and 2005 series champ by the city he had made his home.

In a touching gesture, Castroneves climbed the fence and patted the green and white street sign that reads Dan Wheldon Way before lifting his head skyward and pointing to the heavens.

"You can never question God's mysteries, and today, for me, I ended up stopping at turn 10," said the Penske Racing pilot.

"Honestly, I did not plan it. It was just the way it happened, and there was the sign Dan Wheldon Way. For me, and for all of us - the drivers and the fans - not having him here certainly we'll miss.

Fought

"But we've got to remember him as he lived, the way he lived, and continue to pray for his family."

The victory saw Castroneves, who has won three Indy 500s, become the first three-time winner on the 1.8-mile, 14-turn street circuit and also marked his first win since September 2010 when he clinched the Twin Ring Motegi.

"It's been a little while, but it never gets old," Castroneves said. "I did say out loud, 'If I start in the top six, I'll win this race.' And we did it; we are here in victory circle."

Castroneves finished 5.529 seconds ahead of Scott Dixon, who has finished runner-up in all of Castroneves' wins at the circuit.

Castroneves passed the Target Chip Ganassi Racing driver on the outside of turn one for second place on lap 72.

Three laps later he overtook JR Hildebrand to take the lead and then fought off Dixon to the finish line.

Ryan Hunter-Reay finished third and Andretti Autosport team-mate James Hinchcliffe was fourth.

Ryan Briscoe of Team Penske finished fifth after starting on the front row next to teammate Will Power, who placed seventh.