Not one of the five drivers managed to finish either practice session above the bottom five at Suzuka on Friday.
With Fernando Alonso only managing a high of P17, the Spaniard is expecting to struggle on Saturday afternoon in Japan.
“Since Hungary, we have basically been using Friday sessions to do some tests to ensure that the car for next season works in the right way,” Alonso said.
“This means it’s a little bit more frustrating in terms of finding the best performance this weekend, but it’s good information for the team – and we’ll see tomorrow where we are.
“The weather will play a big factor tomorrow and some rain would help us, as it looks like in dry conditions we’ll suffer.”
Lando Norris made his Suzuka debut, while Vandoorne struggled after missing out on FP1, with both ending up rock bottom.
“It takes you a few laps to prepare every corner because you don’t have time to react so easily to every left-right,” Norris said after the day’s action.
“It does take you a bit of time to get used to, but the whole track put together – especially the whole of Sector One and the beginning of Sector Two.”
“Not being in FP1 gives you a bit of a different approach to the weekend,” Vandoorne added.
“You have to rely on the data the team has gathered during FP1 even though you haven’t been in the car yourself, so you have to trust the direction they’re going in and go with the learning they have done.”
It was a similar story for Williams. Lance Stroll got his Williams the highest but could only slot into P16 in first practice.
The Canadian could only manage P19 in the second session, while Sergey Sirotkin was P19 and P18 respectively.
“We will see what tomorrow brings, there may be a bit of rain, but we have to sort out a few things to be a bit more competitive,” Stroll said after practice.
“I think getting into Q2 will be challenging, but we will try as you never know. For sure rain would be nice just to mix things up.”
“I think we’re in a reasonable position, so if we do everything right, and the conditions suit us, we’ll be on the edge of the Q1 cut-off. It will be a mega job if we do it, but that’s the target,” Sirotkin added to his team-mate’s comments.
Williams remain bottom of the Constructors’ Championship, with just seven points to their name, while McLaren sit in P6 with 58 points, mainly thanks to Alonso’s exploits in 2018.