Carlos Sainz hopes McLaren's disappointing Mexican GP will be a "one-off" after F1's leading midfield team suffered a baffling loss of pace - and a botched Lando Norris' pit-stop - on a frustrating Sunday.
Sainz started seventh in Mexico City and ran as high as fourth - ahead of the Mercedes - in the opening stages but dropped well behind his rivals after his first pit-stop onto hard tyres, and finished down in 13th.
"It was incredible how much we struggled on the hard tyre after making the softs last pretty well, and making such a good start," Sainz told Sky F1.
"We just went backwards. It just the mid-part of the race that killed our race basically. The car felt quite strange today."
For a driver who is seventh in the standings, and a fast-improving team who are comfortably fourth in the constructors' championship - Sunday was a rare blip.
"We've had so many strong weekends and so many strong race days that at some time in the year it's going to happen," said Sainz, although he's confident the unique Mexico conditions mean it won't happen again.
"I think it should be a one-off," he added. "We've been very strong this year on race days so to all of a sudden struggle like we did today is something that we need to learn from. I'm sure we'll find an explanation.
"We need to keep pushing because up until Lap 15 of the race we were dominating again."
What happened to Norris?
Norris, the English rookie, was also running well before the first stop, but his race was ruined in different circumstances.
The front left wheel wasn't fitted properly on his McLaren car when he drove away, he had to be pushed back to the garage to restart the process. After that disastrous stop, Norris was a lap down on the field and McLaren later retired the car.
"It was frustrating because we were in a good position and we could have had good points today," said Norris. "For myself and Carlos it didn't turn out too well, so a frustrating day for the team.
"Everything was going well until the pit-stop."
He continued: "Very quickly you just become deflated and a bit frustrated with everything. But it happens. Normally the team have done a good job with pit-stops and everything so I don't want to complain about them. But it let us down a bit today.
"We just move on to the next pone and try to make sure these things don't happen again."
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