McLaren boss Eric Boullier admits the team failed to "seize the moment" at the Brazilian Grand Prix as it left the wet-weather race with just a solitary point.
The heavy rain and chaotic race which unfolded opened up an opportunity for a strong points and Alonso had been running well before a spin at the final restart. Teammate Jenson Button's torrid weekend culminated in a frustrating race which saw him struggle with handling throughout and finish out of the points.
Racing director Boullier admits the team and its two world champion drivers should have taken advantage of the situation.
"For McLaren-Honda, this was largely a race to forget," Boullier said. "For Formula One as a sport, it's a race from which we can learn in order to improve the show for future wet-weather races.
"Unfortunately for us, neither driver was truly able to seize the moment -- Fernando drove bravely to run inside the top 10 for much of the race, then a lap-56 spin at Turn 13 dropped him to the back of the field. His comeback drive to 10th -- passing seven cars in 15 laps -- was brilliant, and displayed all his speed, bravery and commitment.
"Jenson was unable to rid himself of the handling imbalance he encountered [on Saturday], and struggled to find any rear grip in the tricky conditions. We will go away and examine what went wrong for him."
Alonso, who had to settle for 10th, was also left wondering what might have been.
"I think we were aiming for something better," the Spaniard said. "I started 10th and finished 10th, and there were some retirements in front of me, so we definitely didn't take some of the opportunities that presented themselves out there.
McLaren heads to the season finale in sixth position, 12 points ahead of Toro Rosso.