Alonso, a double Formula 1 world champion, was the star turn as he became the sixth driver to complete the Monaco-Le Mans double after Tazio Nuvolari, Maurice Trintignant, Bruce McLaren, Jochen Rindt and Graham Hill.
Alonso skipped last year's Monaco Grand Prix to tackle the Indianapolis 500, but was forced to retire with an engine failure while battling for the lead. Having now achieved championships in Formula 1 and Le Mans, only the Indy 500 remains.
Toyota are the only team competing with a hybrid auto in the top LMP1 class, and the privateer-run non-hybrids are not fast enough to challenge them.
It was the #3 Rebellion R13-Gibson of Mattias Beche, Gustavo Menezes and Thomas Laurent that finished in third place, standing on the final step of the overall podium, emerging victorious over Rebellion Racing's lead #1 vehicle fronted by Andre Lotterer, Neel Jani and Bruno Senna which was the victim of an accident on the opening lap of the race.
Toyota also claimed a one-two finish, Kamui Kobayashi, Mike Conway and Jose Maria Lopez taking second place in their other auto. A number of penalties in the closing laps meant that it finished two laps down in second place. Both cars ran reliably, with Alonso and his crew running second for much of the opening stint before the Spaniard delivered a stunning spell overnight to reduce the deficit, before Nakajima passed Kobayashi to seize a lead they would never relinquish.
It seemed to be a case of "oh no, not again" for Toyota when Kamui Kobayashi in the number 7 auto slowed down to 80km/h with what seemed like a fueling problem heading towards the end of the race.
The result was never really in any doubt as the number 8 auto qualified on pole and led the race from the outset.
Alonso's auto was left more than two minutes behind the other Toyota but the Spaniard managed to claw back the difference through the night, putting Nakajima in position to retake the lead from Kobayashi early on Sunday. The rules are targeting a 3:20.00 lap around Circuit De La Sarthe, just six seconds slower than the current lap record, set by Kamui Kobayashi in 2017.
His auto was out of contention early on after spending two hours in the pits with an engine problem. Jenson Button's BR Engineering BR1, which included Vitaly Petrov and Mikhail Aleshin, was pulled from the race in the final hour.
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But Manafort has not been sentenced, a judge revoked his house arrest on allegations of witness tampering. Oh, I see, there was no Russian Collusion, so now they look for obstruction on the no Russian Collusion.
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Kimmich lashed over from 25 yards and then Werner went to ground on the edge of the Mexico area, only for play to be waved on. It took Mexico 56 years to win a World Cup opener - their victory coming at the ninth attempt on home soil at Mexico 1986.
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Horses whose pedigrees are based on speed rather than stamina are unlikely to run their best, never mind improve, going 1 ½ miles. Wayne Lukas. "He even looked like he added a few pounds from the Preakness, I mean, this horse just recovers so amazingly quick".
In an era when modern drivers tend to specialise in one category, such is the demand of the individual championships, that it would be a remarkable achievement for Alonso. However, as time has shown, having the fastest vehicle is no guarantee of success.
A Toyota victory had been widely predicted after last year's champions Porsche withdrew from the 2018 edition.
His auto went in to Le Mans as strong favourite and the classic event has now been ticked off in clinical style.
"It was a tense 24 hours, with two cars within a minute for most of the race".
Toyota's win is made all the more special after the team came within a lap of victory in 2016 only to have it taken away from them by reliability issues.
Either way, the win is likely only to enhance his status as one of motorsport's iconic historical figures.
"I went there (the Indy 500) past year without any particular objective".
He will be back in action for McLaren at the French Grand Prix next week, with the race returning to the calendar for the first time since 2008.