Fernando Alonso has made an astonishing claim about his Aston Martin car that shows just how much the team's Honda power unit is holding him back.

After a frustrating early retirement in Mexico City - his seventh of the season - the 45-year-old Alonso got the chance to remind everyone what he was all about at the Brazilian Grand Prix this past weekend, as the wet conditions proved somewhat of a leveller in the F1 field.

Despite clearly being down on power compared to his rivals, Alonso managed to make it to Q3 for the first time this season on Saturday, and although he missed out on the points on Sunday, one moment in particular demonstrated he can still compete with the biggest names in the sport.

As Lewis Hamilton began to go backwards after a flying start, Alonso made an overtake stick on the outside into turn six on lap 10, which, given the track conditions at the time and the Aston Martin vs Ferrari dynamic, was mightily impressive.

Fernando Alonso claims Aston Martin car faster than Mercedes

Unfortunately, in the end it was all for nothing, with the Spaniard missing out on the points and coming home in P12, with Aston Martin still languishing in P10 in the Constructors' standings.

However, post-race, he was incredibly upbeat about his Aston Martin car, claiming that the team could have been one second faster than Mercedes in Sao Paulo if they were not losing so much time on the straights. Of course, as high praise that is for the car itself, it is equally damning for Honda.

"It was probably the best race for the car feeling today," Alonso told the media. "The car was phenomenal on the corners and we were battling with the Ferraris at one point, and even in the last five laps on the inters we were in the mix with the two Mercedes.

"One lap down, but we were in the mix with the Mercedes [in terms of pace]. Taking into account how much we lose on the straight, that means that probably today we could have been one second faster than them per lap.

"So, as I said, the car was phenomenal."

In light of that, Alonso was asked if he enjoyed the weekend a bit more than usual, which he immediately shot down.

"No, I don't enjoy," Alonso replied. "I come, I do my job. There is no fun to drive with different tools. So, working hard to next year close the gap and be a little bit more in a competitive environment."

Same old story at Aston Martin

This is not the first time one of the Aston Martin drivers has made a big claim regarding how much time the Honda power unit is costing them.

Although he didn't reference any other teams, Alonso's team-mate Lance Stroll also claimed that it was costing the team one second per lap at the US Grand Prix in Austin last month.

"The car's not too bad," Stroll told F1TV after the session. "We're missing a lot of power.

"I think we're losing a second [per lap]. That's a lot of time."