Carlos Sainz admits that Ferrari will need to find 'a lot' to salvage its poor Friday performance at the Dutch Grand Prix.
The Spaniard gave way to reserve driver Robert Shwartzman in FP1 as part of the rules around rookie drivers, before climbing back aboard the SF-23 for the second session, claiming 16th fastest 0.7s down on pace-setter Lando Norris.
Teammate Charles Leclerc was 11th quickest, 0.2s quicker than Sainz, who branded the day "tough" for the Scuderia.
"When I jumped in the car obviously it wasn't an easy session, getting back up to speed is never easy at Zandvoort," Sainz explained to F1TV.
"Unfortunately, we don't look very competitive. We're going to need to find some lap time, find some downforce, find some balance because it was a tough for the team."
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Sainz identifies problems
Sainz believes that the SF-23 has an inherent problem at certain circuits, which is exacerbated by the short lap time around Zandvoort that tightens the field up.
"I think we saw something similar in Hungary now where we go to higher downforce tracks," he said.
"For some reason, we don't pick up as much downforce as maybe the others when we go into the bigger rear wings. We are trying to find out why and it is bit of homework on our side.
"We want to be fighting for the podium [in the race but it] needs a very big jump in performance [to achieve that].
"We didn't put a lap together and I've only done one session so there is margin for improvement."