Lewis Hamilton has revealed how smart race tactics enabled him to keep Sebastian Vettel behind him when the Belgian GP restarted and the pair went head-to-head for victory.
While Hamilton still held track position when the grand prix resumed after a Safety Car period with 15 laps to go, Vettel had the advantage of running the ultrasoft tyres compared to the Mercedes' softs.
As the pair emerged at the top of the hill having hurtled nose-to-tail through Eau Rouge, Vettel briefly appeared alongside the Mercedes.
But Hamilton said that he had deliberately allowed Vettel to stay close to him before the Kemmel Straight so that the Ferrari would spend as little time as possible in his slipstream.
Admitting his initial restart "wasn't great", Hamilton told Sky Sports F1: "I had power in the wrong setting so as I pulled away I didn't pull away as I hoped.
"Then he was on my tail into Turn One, struggling with the front tyres and he was too close at the exit at Turn One so he had to lift. Which was actually great.
"Going down the straight [between La Source and Eau Rouge] I let off the power a little bit as well just to keep him on my tail. If he was further away he would have had the chance to gain momentum and pass on slipstream and that's what he would have wanted so I didn't give him that.
"So when we got to the top of the hill and he was there, he was facing the full force of the air just as I was so he had no hope. I was really pleased with that move."
In the pre-podium holding room, Vettel said to Hamilton "that was close" as they watched a replay of their duel, to which Hamilton replied: "I lifted, that's why you were close."
The Mercedes driver later said he had been running at 90 per cent full throttle.
"As we were going up Eau Rouge I gave it full power and he had no space to really propel himself and he just pulled out alongside," Hamilton said.
"It was a cool battle. After that it was nine or 10 laps of qualifying - heavy, fast laps as he was very quick and I had to do some very fast laps to stay ahead.
"I was just thinking I want to win this race. I've come here, I've told you what I'm coming here for and I'm not leaving here without it. It was a real aggression feel."
Vettel suggested his restart was possibly "too good" as he got right up behind Hamilton into La Source.
The Ferrari driver added he was then waiting for a mistake from Hamilton which never came.
"I knew that we had a tyre advantage for the first couple of laps after the restart," said the championship leader. "Exiting Turn One I was all over Lewis and it was not too hard to follow him. Maybe it was too good.
"Overall it was a very good race. It was good fun in the car because I was waiting for him to have an error and he probably was waiting for me to have an error. The quality was very high. I never really had a chance."
Meanwhile, Mercedes boss Toto Wolff has credited the team's decision to use soft tyres for the final leg of the race along with a strategic decision to sacrifice qualifying performance as critical ingredients in Hamilton's win.
On Mercedes' tyre decision, Wolff said: "We expected the soft to be the faster tyre for the final twelve to fourteen laps, depending on how long the Safety Car stayed out for. The ultrasofts were a good option for two laps of attack after the restrart but then not the right tyre.
"There were lots of discussions about it. I was worried. James Vowles wasn't and he is the one who knows - or the pitwall knows. But he was quite convincing and it proved to be right. But the gut decision was the ultra."
Wolff also expressed his relief that the team's decision to give up performance in Spa's twisty middle sector to maintain a superior top-end speed had been vindicated by Hamilton's ability to fend off Vettel's attacks in a car which the Englishman felt was quicker.
"We gave up qualifying performance in the second sector," Wolff explained. "We opted for a set-up which would be the faster race set-up. The sacrificed downforce for qualifying which means we left lap time on the table in the second sector, in order to have the quicker car in sectors one and three. That proved to be the right decision. Ferrari had more downforce and more drag and that, with all the tools and modes we had, made him stay in front."