Lewis Hamilton has forecast Ferrari would finish one-two if the Bahrain Grand Prix was staged this weekend.
The Scuderia is slowly starting to emerge as the team to beat with only one day of pre-season testing remaining going into the season-opening race in Bahrain next weekend.
At the conclusion of the second day of testing at the Bahrain International Circuit, Carlos Sainz was second quickest with a lap of one minute 33.532secs, half-a-second clear ahead of Red Bull's Max Verstappen.
Sainz was given a favourable tow by Hamilton over the second half of the lap, but regardless the F1-75 would appear to be the most stable car at present.
Pressed on a likely outcome of the race if the grand prix was this Sunday, Hamilton replied: "From what I can see, Ferrari would probably be getting a one-two, and maybe Red Bull."
Mercedes trying to "tame" Hamilton's car
As for Hamilton and Mercedes, he is adamant the W13 has issues, noticeably with the porpoising as the car was seen bouncing violently along the straight on various occasions.
"It's definitely tough out there," added Hamilton. "It's windy and the wind changed around quite a bit today but generally it's been tough.
"If anything it [the bouncing] is a bit worse, so we're just working through lots of different scenarios, trying to figure out how to hold on to the downforce and not have it bouncing as we saw in the last test and now you're seeing here.
"Everyone is in a similar boat. Some have managed to get around it in a better way but it's difficult out there.
"It's bumpy, it's slippery, there's sand, in the morning it's way too hot, and in the afternoon, it's just gusty.
"You can see from the onboard, [there are] tank slappers left, right and centre, you're bouncing and bumping, so not quite happy at the moment but we're trying to tame her."