Fernando Alonso is confident the pain of the United States and Mexico City Grands Prix is now firmly behind Aston Martin and it now has a platform on which to build into next season.

For those two races, especially at the Autodromo Hermanos Rodriguez, Aston Martin appeared lost following the introduction of its latest upgrade ahead of the event at Austin’s Circuit of the Americas.

The sprint weekend format for the USGP complicated matters for the team as it only had one practice session to assess the cars before they were locked down under parc fermé conditions following qualifying on Friday evening.

The crucial need to make changes on the AMR23s after Saturday’s sprint day and ahead of Sunday’s grand prix, though, forced Aston Martin to break parc fermé, resulting in both Fernando Alonso and Lance Stroll starting from the pit lane.

Alonso retired late on, whilst Stroll at least salvaged the weekend by taking the chequered flag in ninth before being promoted to seventh following the disqualifications of Mercedes’ Lewis Hamilton and Ferrari of Charles Leclerc.

Worse followed, however, in Mexico City where the car lacked pace and performance, culminating in Stroll qualifying 18th and Alonso 13th, leading to the team again making changes for the Canadian and another pit lane start.

Both cars retired due to collision damage, albeit Stroll was classified 17th and last as he exited the race with five laps remaining.

In the São Paulo Grand Prix, however, the team finally unlocked performance from its car again, with Alonso stepping onto the podium for the first time since the Dutch GP at the end of July following a stunning late battle with Red Bull’s Sergio Perez, whilst Stroll was fifth, his second-best result since finishing fourth in Australia in early April.

“We’ve been struggling for a few months,” conceded Alonso after his result in Brazil. “The last two races (US and Mexico) were probably quite painful.

“We had to experiment a little bit with a few things on the car to really understand the direction we were going, and we have to go for next year’s car as well. So those races were painful, especially Mexico. We were very slow as a team.”

Recognising the commitment from within in order to turn the Aston ship around, the two-time F1 champion added: “It was nice to see everyone in the team very focused, determined, united in the same direction, going deep into the analysis and coming back stronger in Interlagos.

“I was a little bit concerned, no doubt, for the last few races, the final part of the championship, but now I cannot wait to go to Vegas. So it’s a very different energy when you have a performing car.”

The inaugural race around the City of Lights unfolds next weekend on the back of F1 pumping millions of dollars into the event as it promotes a grand prix for the first time.

The 17-turn, 6.201-kilometre track, that incorporates the Strip will prove a leveller for all concerned given it is such an unknown quantity, with the cold air and track temperatures also playing a significant role.

Alonso heads to Las Vegas at least buoyed by what he felt from the car in São Paulo, although mindful there were mitigating circumstances that propelled him back onto the podium, and so has warned against a repeat.

Assessing whether his form around Interlagos would spill over into the final two races of the year, with Vegas followed swiftly by the curtain-closer in Abu Dhabi, he replied: “I think so.

“There are a couple of things that have been understood inside the team and the direction to go. We had some hopes (for Brazil), and they proved to be right. Now, why not be competitive in the last two?

“I don’t know if (it would be) the level of the podium. We had Charles (Leclerc), obviously, going off on the formation lap with a problem.

“We had the Mercedes underperforming, Checo (Perez) starting at the back, so there were a couple of factors that helped us to be on the podium. Hopefully, we will be in the mix. That will be a happy place for us.”