His pole position may have been a gift thanks to Friday's inclement weather conditions at Twin Ring Motegi but Helio Castroneves certainly earned his second consecutive IRL IndyCar Series win on Saturday.

The Brazilian born Marlboro Team Penske driver was able to take his fence-climbing road show overseas for the first time since joining the IRL, dominating the 200-lap Indy Japan 300 and completing a rain-hit weekend that saw him lead every practice session that he participated in.

From the front row of the grid, Castroneves was able to open up an early advantage and stay ahead of his pursuers through a pair of back-to-back caution flags in the first 60 laps that thinned the starting field from 20 to 15, thankfully without injury to any of the drivers involved.

He then stretched his legs during a lengthy green flag run, leading the pack by a secure margin and only losing the lead during a round of green flag pitstops at two-thirds distance.

With that round of pitstops also helping to reduce the number of Castroneves' closest challengers, the third and final caution of the day on lap 155 gave the remainder of his rivals one final stab at glory.

However after soaking up some early pressure, notably from Homestead winner and double defending Motegi winner Dan Wheldon, Castroneves was once again able to ease away as the final 35 green flag laps unfolded without further incident and eventually took the chequered flag with an almost unheard of (in IRL oval races) seven second advantage over runner-up Wheldon.

Not only does Castroneves' ninth career IRL win strengthen his early season points lead, it also gives the popular Brazilian driver the perfect momentum going into next month's Indy 500 where he will undoubtedly start as one of the favourites.

Most of the excitement came behind Castroneves, as drivers jockeyed for position to lead the chase. Andretti-Green teammates Dario Franchitti and Tony Kanaan started off ahead before being overhauled by Target Chip Ganassi duo Wheldon and Scott Dixon.

Working together, the two red and white cars in second and third were able to close in on the red and white car at the head of the field but although Dixon was able to draw alongside Castroneves once on the run towards turn three, he was never able to get his nose ahead.

Dixon's charge effectively ended during the above-mentioned green flags stops when he stalled his #9 Dallara-Honda as did Franchitti's, who clipped two of his crew-members and lost several laps as the team scrambled to get through the service. Although both drivers would finish the race, they would do so well down the order.

Wheldon did his best to take advantage of the last caution, shadowing Castroneves for several laps before fading back to a still-comfortable second place, more than two seconds ahead of third place man Kanaan and Castroneves' Penske teammate Sam Hornish Jr.

Fourth place may equate to a solid points haul for the double IRL Champ, but for the third race in a row Hornish Jr had to play a distinct second-fiddle to his teammate.

Buddy Rice completed the top five after a strong late race surge in one of only three Panoz chassis in the race with Bryan Herta sixth, home crowd favourite Kosuke Matsuura an excellent seventh and Danica Patrick a gritty eighth in the sister Rahal-Letterman entry to Rice.

Dixon headed home the lapped runners in ninth place with Vitor Meira completing the top ten and Franchitti leading home his rookie teammate Marco Andretti in eleventh and twelfth places respectively.