Sainz led the midfield teams in qualifying to take P5 on the grid, and made a good start to pass Sergio Perez for fourth on the opening lap.
But following a safety car period, Sainz slipped behind Perez and former McLaren team-mate Lando Norris before pitting for a set of medium tyres at the end of lap 21.
It caused Sainz to struggle in the closing stages as the majority of cars around him opted to run hard tyres for the second stint, leaving him unable to fend off attacks from cars behind.
After moving aside to let team-mate Charles Leclerc pass, Sainz lost positions to Esteban Ocon, Fernando Alonso, Daniel Ricciardo and Pierre Gasly in the closing stages, dropping out out of the points to P11 at the chequered flag.
Carlos Sainz Jr., Ferrari SF21, Charles Leclerc, Ferrari SF21
Photo by: Andy Hone / Motorsport Images
“Hindsight is a beautiful thing, and on hindsight, clearly the hard today was simply a stronger tyre, particularly on our car,” Sainz explained after the race.
“We struggled a lot with the mediums, and we need to still understand why we were so prone to graining on that medium tyre, why the combination of the medium with our car was just not working well today.
“In hindsight, for sure we would have done things very differently, but with the data we had available before the race, we thought that a soft/medium strategy was going to be OK, and it clearly wasn’t.
“A lot to analyse and a lot to go through now in these next three or four days. I’m sure we will take the right conclusions and improve going forward.
“I know that today, it was in our hands and in my hands to score a top-five, top-six result with a decent race execution and the pace we’ve shown all weekend.
“So to come out with zero points and an 11th place, it’s difficult to think about the positives.”
Ferrari team principal Mattia Binotto explained after the race that the team could see how much graining was impacting Sainz during his second stint, prompting the call to allow Leclerc to pass.
Leclerc went on to finish the race in sixth place, five seconds behind midfield leader Norris.
“Swapping positions is something that we would like to avoid, things that are normally aren’t great, but sometimes maybe necessary,” Binotto said.
“Today, we felt it was because of different pace, and we could see that Carlos was suffering with the graining of the medium. We asked to him, he did it immediately.
“So it seems it really talks to the way he understands the message. I think when you’ve got drivers that understand what’s the priorities and that support the team, it’s always a pleasure.”