Somkiat Chantra completed his masterclass around the Motegi Twin Ring circuit as he turned dominance during Practice and Qualifying into an equally emphatic race victory in the Japanese Moto2.

A class above throughout the weekend, the Thai rolled out a crushing lights-to-flag victory in Sunday's all-important race to ensure a rare clean sweep of the entire race weekend; top times in all three Practice sessions, pole position, fastest race lap and race victory.

A venue he knows well from his time competing in Asia prior to joining the international stage, Chantra’s success represents the second Moto2 victory of his career in the intermediate class, the first having come in Indonesia last season.

Better still, with Ai Ogura chasing him home in second place, IDEMITSU Honda Team Asia got to celebrate a welcome boost of a 1-2 result on home soil, a result that will energise the team in a season that has by and large failed to meet expectations.

In the fight for the Moto2 title, Pedro Acosta picked up more valuable points in third at the behest of Tony Arbolino, who could only manage 11th after a scruffy race. It means the Spaniard has extended his margin out front to 50 points with six events remaining.

However, the day - and the entire Japanese Moto2 weekend - belonged to an exceptional Chantra, his dominance over the three-days even extending to him getting the perfect start from pole position to get the hole-shot into Turn 1.

It would prove decisive for him too, Chantra getting his head straight down to pull away from chasing pack too busy tripping over itself during the initial turns.

Almost a second clear by the end of lap two, the margin would swell to +1.9secs at the end of lap three, +2.1secs by lap six and +2.3s once the riders had rounded lap eight. Though the margin would stabilise from here as Chantra eased up his relentless pace in front, it would ultimately do enough to put a fight for victory out of the question early on.

And so it proved, Chantra managing his margin once team-mate Ogura had worked his way into second place to take the flag for the win. The Japanese might have stood a better chance of challenging Chantra had he not gotten bottled up behind Alonso Lopez early on, a particularly frustrating situation given the Spaniard was always due to serve two long lap penalties anyway.

By the time he was through again, Chantra was too far up the road but second place at least completes a historic day for the home favourites, as well as mark his second podium of the season.

Acosta too may have also been up for a fight against Chantra but after saving a bad getaway with a sweeping wide line into Turn 1 that had him in second, an aggressive lunge up the inside by an impatient Aron Canet on the exit would force the KTM Ajo rider down to seventh again.

Though he’d make light work of the riders ahead to get back into the top three, Acosta had no answer to the Honda Team Asia duo ahead. Still, he still enjoyed a far more lucrative afternoon than main title rival Arbolino, the Italian suffering another Sunday lull on the Marc VDS Racing machine.

From 12th on the grid, Arbolino got embroiled in the busy mid-pack, yo-yoing around the top ten for a time before an error with seven laps remaining left him playing catch up. He’d eventually cross the line 11th but faces an uphill task to get on terms with Acosta in the title race now.

Indeed, there is now a smaller margin between Arbolino in second and Jake Dixon in third overall now (43 points), the Briton having steadied a ship that went awry in Misano and Buddh to shadow Acosta home in fourth place for more valuable points.

Another rider bouncing back to form after a run of lacklustre races, Filip Salac returned to the top five in fifth place, holding off Manuel Gonzalez, who took sixth after taking advantage of a crash just ahead for Sergio Garcia.

In seventh, Marcos Ramirez continued his superb form since jumping ship to American Racing after the summer break, the Spaniard picking up another season’s best result for the US squad.

Canet crossed the line in eighth place, his afternoon having been hampered by first nudging Acosta at Turn 1 before another mistake later round the opening lap left him fighting back from a low of 13th.

He got the edge on Zonta van der Goorbergh, who just seven days after breaking his Moto2 points’ duck in India - a fine sixth place at the 31st attempt - made it back-to-back top ten results with a run to ninth place. 

Darryn Binder completed the top ten on the Husqvarna IntactGP machine, ahead of Arbolino, who just got the better Joe Roberts, the penalised Lopez in 13th, Izan Guevara in 14th and Barry Baltus in 15th for the final point.

A race of low attrition, alas Sam Lowes counted himself as one of the retirees after dropping his bike on the exit of the Turn 14 final right-hander while running sixth.