Last week's Bahrain jubilation has made way for a bit of worry for Pierre Gasly following a "massive step back" in performance for Toro Rosso in qualifying on Saturday.
The Frenchman endured a low profile session which left him well down the order in seventeenth, two spots behind team mate Brendon Hartley.
Gasly was hard pressed to explain his STR13's sudden lack of pace between yesterday's free practice sessions in Shanghai and Saturday.
"We knew top 10 would be difficult, but expected to be around P11, P12, and actually to be a couple of tenths behind," Gasly said.
"I think today we made a massive step back compared to yesterday, we lost a lot of performance, and that's what we didn't really expect."
Gasly said that the changes made overnight to improve the car's balance had actually gone in the opposite direction, and in a much bigger way than expected with massive oversteer and a lack of traction.
"We made some changes and completely changed in terms of balance, it's completely opposite of yesterday, we lost all the strength of the car we had in the package, and [it's] just super tricky.
"I almost crashed in Turn 8 this morning, I almost crashed in Turn 10 as well. Just massive loss of rear grip. And yesterday it was actually our strength - good stability."
Team mate Brendon Hartley reckoned that Shanghai's cold and changing conditions may have played their part in the STR11's inconsistency.
"I don't think many places higher up the grid was possible, we don't have anywhere near the same performance compared to other competitors that we did in Bahrain," Hartley said.
"My personal opinion is that the temperature and the wind is the two biggest factors - not saying I have the answers but it seems to be a trend, it happened in Australia in the race as well.
"Every other time that it's been hotter we've been more competitive, and every time it's been windier we seem to suffer a lot more than others.
"Aerodynamics on a Formula 1 car are very complicated and when you have wind it really messes with aerodynamics, we seem to struggle.
"The good news is we know we have potential in the car but it's just about unlocking it in every scenario."