Lewis Hamilton dominated the Canadian Grand Prix as dramatic action behind allowed him to cut his points deficit to Sebastian Vettel.
The Mercedes driver controlled the race from start to finish, leading home team-mate Valtteri Bottas, while Vettel could finish only fourth in the Ferrari, his championship lead cut by half to 12 points.
Vettel dropped to the back when he needed to change his front wing, damaged by Red Bull's Max Verstappen at the start.
He recovered well with some aggressive over taking on a two-stop strategy and caught the battle for third place, in which Red Bull's Daniel Ricciardo was leading the Force Indias of Sergio Perez and Esteban Ocon, with seven laps to go.
Vettel passed Ocon in a touch-and-go move into Turn One with four laps to go. An off-track moment a few corners later dropped him back from Perez but he made an aggressive move into the last corner with two laps to go.
Hamilton vs Vettel - a battle denied
Hamilton and Vettel qualified alongside each other on the front row and were expected to stage a close fight in the race for superiority in a race the Mercedes driver really needed to win to boost his title hopes.
But the grand prix fell into Hamilton's lap within a few seconds of the start.
Verstappen made an electrifying getaway from fifth place, threaded his way between the Ferrari of Kimi Raikkonen and Mercedes' Valtteri Bottas and swept around the outside of Vettel into the first corner.
But the Dutchman slightly misjudged the move, and his left rear wheel clipped Vettel's front wing as he claimed the corner.As Verstappen forced his way up to second at the first corner, he clipped Vettel's front wing, effectively ending his challenge
The chaos which shaped the race
Shortly afterwards, Toro Rosso's Carlos Sainz tangled with Haas' Romain Grosjean on the curving straight between Turns Two and three and the Spaniard lost control, spinning down the inside of the track and side-swiping Felipe Massa's Williams in Turn Three, forcing Fernando Alonso's McLaren on to the grass in avoidance.
That brought out the safety car for four laps but Ferrari waited until the restart on lap five to bring in Vettel and change his front wing and fit a set of super-soft tyres.
The plan may have been to try to get to the end on that set, but this was abandoned on lap 49, by which time Vettel was up to sixth place.
Ferrari chose to stop Vettel again in the hope he would have fresher tyres and be able to catch and pass the cars battling for third place behind Hamilton and team-mate Valtteri Bottas.
Their predictions that he would catch Ricciardo/Perez/Ocon with eight laps to go were spot on and it led to an entertaining and frantic battle from which Vettel emerged the victor.Carlos Sainz crashed on the first lap after fighting with Romain Grosjean
Hamilton in control
Vettel's problems left Hamilton in a league of his own.
He cruised away from Verstappen in the opening laps, and when the Red Bull retired with an engine problem on lap 11, Hamilton had a comfortable pace advantage over Bottas.
He simply drove away unchallenged to his third victory of the year, prompting team boss Toto Wolff to say it was a "stellar" drive and one of his best performances in more than four years with the team.Lewis Hamilton grew up idolising Ayrton Senna - now he has his helmet - after equalling the Brazilian's pole position record of 65
There may be recriminations at Force India as Perez refused requests to allow Ocon past in the closing stages so he could try to pass Ricciardo.
Perez spent the entire race behind Ricciardo without ever getting close enough to try a passing move.
The team decided Ocon, who appeared to have stronger pace, should be allowed to try to make progress. But Perez had other ideas.
The Mexican demanded the team "let them race" and it led to a heart-in-mouth climax to the race for the team.
There were several dicey moments as Vettel closed in, Ocon's attempted pass into the final chicane allowing the Ferrari to close up and pass the Frenchman into the first corner on lap 65.
Ocon missed the corner, and took to the escape road, but charged back onto Perez's tail.
They raced side-by-side into the last corner on the last lap, Perez defending hard, and holding his team-mate off.
Ocon was not amused. "This is not fair, guys," he said over the radio. "He moved at the last minute. He cannot do that. This is not fair racing at all."
Stroll in the points, Alonso in the crowd
Behind the Force Indias, Raikkonen nursed his Ferrari home with brake problems in the closing stages, ahead of Renault's Nico Hulkenberg and Canadian Lance Stroll, who scored the first points of his debut season for Williams at his home race.
Stroll was holding off McLaren's Fernando Alonso in the closing laps. The Spaniard appeared set for the team's first point of the year for 10th place but he retired with yet another Honda engine failure with two laps to go.
The Spaniard threw his cockpit protection out of the car, got out and jumped straight into the crowd to posh for pictures with delighted fans.
That will only increase the tensions at McLaren, where divorce from Honda appears to be on the cards in just the third year of a long-term contract.Teams took part in a traditional raft race in the water surrounding the track ...and it was McLaren who took the top step on the podium - enough to convince Alonso to stay? Movie star Michael Douglas attended the race The Canadian Grand Prix takes place on a man-made island in Montreal