Lewis Hamilton scored a second North American win in as many weeks after repelling McLaren team-mate Fernando Alonso's advances during a tense race-long duel at Indianapolis.
It was another consummate performance from the 22-year-old British rookie, who soaked up enormous pressure from the double world champion as the McLaren duo waged their most intense and uninhibited battle yet.
Halfway through the race, the team-mates came just inches away from contact as they raced side-by-side down the long pit straight.
But they gave each other just enough room, Hamilton retained the lead, and the die was cast for the rest of the afternoon.
Unlike last year, there was no wholesale carnage in turn one on the first lap - but it did get scrappy as Ralf Schumacher locked up his Toyota's front wheels and slid into an innocent Rubens Barrichello (Honda) and David Coulthard (Red Bull), sidelining all three cars.
Simultaneously, BMW's F1 debutant Sebastian Vettel, perhaps getting distracted by the commotion to his right, took to the grass and lost several places.
Meanwhile Hamilton had successfully used a defensive line to convert pole into the lead into turn one, and then staved off the marauding Alonso around the rest of the opening lap.
Having kept Fernando at bay, Lewis set about controlling the race from the front, gradually eking out his lead to 2.2s by lap 10.
Felipe Massa held third off the start but Ferrari team-mate Kimi Raikkonen lost two places, to Nick Heidfeld's BMW and Heikki Kovalainen's Renault.
Giancarlo Fisichella moved up two places to eighth but threw it all away when he touched the grass under braking for turn four on the second lap, throwing his R27 into a spin.
The Italian's mistake seemed to fire him up and he began the kind of feisty recovery drive we saw at Monaco in 2006.
The highlights included a side-by-side tussle with Jenson Button that went on for three corners, and a muscular move inside Alex Wurz at one of the infield hairpins.
At the front of the field Hamilton was still looking strong, extending his lead to more than three seconds before initiating the pit stops on lap 21.
Alonso pitted one lap later but was unable to capitalise on a shorter stationary time due to slower in- and out-laps, leaving Hamilton's lead virtually unchanged.
Massa was still running third, but Heidfeld had lost fourth immediately before his stop when he spun into the escape road under braking for turn one, allowing Kovalainen to nip past.
The Renault driver had been fuelled for a long first stint and now enjoyed his first spell in the lead of a grand prix.
Apart from affording him that privilege, the strategy didn't really pay off and after taking on service on lap 27 Kovalainen rejoined behind both Raikkonen and Heidfeld.
Meanwhile the battle for the lead was really hotting up.
Three slow laps for Hamilton while the Briton was stuck in traffic gave Alonso the opportunity to whittle away his lead, and by lap 34 there was just 0.7s between them.
As they closed on the long line of cars led by 11th-placed Vitantonio Liuzzi, Alonso's car grew ever larger in Hamilton's mirrors.
By the time they emerged onto the main straight on lap 38, the team-mates were absolutely nose to tail, with Alonso pulling out of the slipstream to challenge for the lead.
What followed was a riveting few seconds of wheel-to-wheel action (with echoes of the Mansell-Senna dice at Barcelona in 1991), as Lewis defended the inside and Fernando braked as late as he dared on the racing line.
Hamilton held his nerve, won the corner - and Alonso's best chance was gone.
The Spaniard probably knew as much, showing his displeasure by veering towards the pit wall next time by in what seemed a rather futile gesture to his McLaren mechanics.
Several laps later, when he was still within close range, he lost a second with a ragged moment at turn eight, giving Hamilton vital extra breathing space.
The reason for Alonso's frustration became evident on lap 50, when he was the first of the McLaren drivers to make his second pit visit.
Barring any unforeseen late hiccups, Hamilton now had the race in his pocket - and so it proved.
The margin between the two silver cars fluctuated around the 2s mark through most of the final stint, Hamilton eventually taking the chequered flag 1.5s in front.
Massa had to fight a rearguard action in the closing stages to fend off a charging Raikkonen, who had recovered well from his poor start and looked much more like the Kimi of old.
Unlike the other front-runners, the Finn had started the race on the harder of the two tyre compounds and had soft rubber for the last stint.
Massa's defence was impeccable and the Brazilian held on for third place - but Raikkonen set the fastest lap of the race, which will have given Ferrari some cause for encouragement in the face of another McLaren 1-2.
A week after dodging the Montreal carnage for fourth place, Kovalainen came home fifth on merit after a morale-boosting US Grand Prix weekend in which he generally outpaced team-mate Fisichella.
Heidfeld might have had something for him, but the German fell by the wayside on lap 56 with a hydraulic problem.
Sixth place should have gone to Nico Rosberg, who drove a strong race on a one-stop strategy - but the Williams succumbed to an oil leak and he pulled off in a cloud of smoke with just four laps remaining.
His demise elevated the battling trio of Jarno Trulli, Mark Webber and Vettel to the final points-paying positions.
Trulli and Webber enjoyed a spirited dice that was decided in the Italian's favour after the Australian's lunge down the inside of turn one ended in a trip across the infield grass.
It was a banner day for 19-year-old Vettel, who drove a mature race after his first-lap excursion to become the youngest points-scorer in F1 history.
For once, someone other than Lewis Hamilton was rewriting the record books.
But that won't have bothered F1's star rookie as he completed a dream North American double.
Fastest lap: Raikkonen 1m 13.117s
* Being lazy, this was borrowed from itv and then edited