Daniil Kvyat has said that the team will have to investigate their lack of speed after they struggled to perform in Baku. Toro Rosso have performed well so far this season but will be hoping to bounce back from their blip in Azerbaijan.
"We lost a big amount of grip all of a sudden," said Kvyat to Autosport about a difficult first stint that included a drop from sixth to 12th in the first five laps.
"It was like a big warning. So we think we got something slightly wrong. I don't know whatever it is, but we need to analyse it now and we can learn from it."
"When we pitted for the yellow [medium] tyre, C3, it wasn't looking too bad," said Kvyat.
"The pace still wasn't excellent enough to match perhaps McLaren, but we were hanging there.
"We were still in a race for a point or a couple of points, and obviously Daniel caught [me].
"I was aware he was going to catch me sooner or later. So honestly he just had to be a little bit more patient and it wouldn't have been an issue.
"It's a shame, but we need to investigate why we were so competitive throughout [practice and qualifying] and we lost all of a sudden the pace [in the race].
"I am sure our guys will be on it and we'll be better next time."
Toro Rosso are 9th in the constructors championship, 4 points behind Haas and they will hope to close them down in Spain.