The Briton was up against it right from the start after enduring a difficult qualifying session 24 hours previously.
Hamilton performed well enough but it wasn't enough to challenge Max Verstappen, with the Red Bull driver securing an 18th win of the campaign.
And the Stevenage-born racer has now apologised for the way he drove on Saturday when speaking after the main event.
Lewis Hamilton was unable to challenge Max Verstappen at the F1 Las Vegas Grand Prix
"Apologies to the whole team for qualifying yesterday," Hamilton told Sky Sports F1.
"There are strengths within our car but sometimes sometimes sometimes it's just really difficult to get the performance out of it."
Hamilton wasn't alone in struggling at times during the race.
George Russell collided with Verstappen and was slapped with a penalty as a result.
The 25-year-old lamented his failure to finish higher, having started the day in fourth.
"Just another massively missed opportunity this weekend," he said.
"The incident with Max was totally my fault. I didn't see him. Totally in my blind spot around Turn 11.
"I wasn't really expecting the overtake there because you've got the big long straight with DRS afterwards.
"We were on course for an easy podium. It was pretty straightforward. Recovered to P4 but the five seconds knocks us down to P8.
"This season is one thing after another. Ultimately, the pace was strong but not as strong as the Red Bulls and Ferraris.
"I think when you have a fast car, luck is always on your side and when you're on the back foot, luck is never on your side.
"Ultimately, we just need to keep on pushing, go into next week and see what we can do."
Verstappen, meanwhile, revealed he had a 'lot of fun' - despite previously criticising the decision to stage the race in Vegas.
"It was a tough one. I tried to go for it at the start," the three-time World Champion said.
"We (himself and Charles Leclerc) both braked quite late and I just ran out of grip, so we ended up a bit wide.
"The stewards gave me a penalty for that and it put us on the back foot.
"I had to pass quite a few cars and there was the Safety Car, so at that point there was a lot going on.
"Then we went flat out. I had to pass a few cars to get into the battle with them.
"The DRS around here was very powerful. Even when you would take the lead, if the guy behind stays in the DRS, he would still have the opportunity to come back to you, so it created a lot of good racing today.