Mercedes showed in Shanghai on Friday that they were up for the challenge from Ferrari as Lewis Hamilton was quickest, but the Scuderia are not going away quietly.
After being stunned by Sebastian Vettel and Ferrari on race day in Malaysia last time out, Mercedes have spent the best part of the past two eeks insisting that they will up their game.
And they did just that in Free Practice as Hamilton was more than a second faster than the Ferraris in FP1 and the defending World Champion was once again too good for the rest of the pack in FP2.
He initially led the timesheets with a 1:39.058 on the medium tyres, but Kimi Raikkonen in the Ferrari was the first to venture out on the softer rubber and the times dropped pretty quickly.
In fact the Finn chopped two and a half seconds off his own time and jumped to the top with a 1:37.662. Rosberg was next to go out, but the German lost it at the exit of the final corner and could only manage P2, which became P3 when Vettel produced a 1:38.339.
All eyes were on Hamilton though, and he didn't disappoint as he eased to the top with a 1:37.219, which was 0.443s faster than the time of Raikkonen.
However, Ferrari hit back during the longer runs as Raikkonen matched Rosberg in terms of times on the medium tyres while Hamilton just edged Vettel on the softer rubber. So we should be in for another close battle come Sunday.
Red Bull are another team who are hoping to hit back after a disappointing weekend in Malaysia and Daniel Ricciardo showed they will be there or thereabouts as he slotted in at P3 with a 1:38 to push Vettel and Rosberg down while Daniil Kvyat was P6.
Kvyat had a premature end to his session after his left-rear brake caught fire following a trip to the pits. He was told to nurse his Red Bull back to the garage, but the brakes failed and he ended up in the gravel and nudged the barriers.
Then you had Valtteri Bottas, Felipe Nasr, Romain Grosjean and Jenson Button completing the top 10.
No, that is not a mistake with Button's name there as McLaren continued to move in the right direction as the Brit produced a 1:39.275 while Fernando Alonso was down in 12th place.
Meanwhile, Bottas' Williams team-mate Felipe Massa had a scary moment in FP2 as he just clipped the barriers and brought out a red flag, albeit for a very brief moment. The Brazilian lost the rear end of the car under braking and went sliding off the track. He later held up his hand and admitted it was driver error.
It was also a disappointing day for the Toro Rossos and Force Indias with Nico Hulkenberg suffering a gearbox issue late in the session, while the Manor pair of Roberto Merhi and Will Stevens were bottom of the timesheets as expected.
1 Lewis Hamilton Mercedes 1:37.219 32 laps
2 Kimi Raikkonen Ferrari 1:37.662 0.443 35 laps
3 Daniel Ricciardo Red Bull 1:38.311 1.092 24 laps
4 Sebastian Vettel Ferrari 1:38.339 1.120 30 laps
5 Nico Rosberg Mercedes 1:38.399 1.180 35 laps
6 Daniil Kvyat Red Bull 1:38.737 1.518 10 laps
7 Valtteri Bottas Williams 1:38.850 1.631 27 laps
8 Felipe Nasr Sauber 1:39.032 1.813 26 laps
9 Romain Grosjean Lotus 1:39.142 1.923 32 laps
10 Jenson Button McLaren 1:39.275 2.056 29 laps
11 Pastor Maldonado Lotus 1:39.444 2.225 30 laps
12 Fernando Alonso McLaren 1:39.743 2.524 27 laps
13 Marcus Ericsson Sauber 1:39.751 2.532 33 laps
14 Max Verstappen Toro Rosso 1:39.894 2.675 32 laps
15 Carlos Sainz Toro Rosso 1:39.971 2.752 28 laps
16 Nico Hulkenberg Force India 1:40.151 2.932 28 laps
17 Felipe Massa Williams 1:40.423 3.204 7 laps
18 Sergio Perez Force India 1:40.868 3.649 24 laps
19 Roberto Merhi Manor 1:42.973 5.754 27 laps
20 Will Stevens Manor 1:44.564 7.345 8 laps