Is F1 finally set for its big-three battle royale?

Tense and dramatic as the Bahrain Grand Prix was, we've yet to see the race everyone has been hoping for in 2018: Mercedes, Ferrari and Red Bull going at it at the front of the field. Friday practice in China hinted that we might get just that at the third attempt.

As in Bahrain, it seems Mercedes and Ferrari are both in with a shot at pole position and, on race pace, Red Bull has the chance to join that mix. In fact, using every metric available on the outside, it looks incredibly close between the big three - with a tenth here or there likely to make all the difference.

The qualifying battle looks to favour Mercedes on paper. But while Lewis Hamilton was fastest overall during Friday practice, he was only seven thousandths of a second faster than Ferrari's Kimi Raikkonen.

Given Raikkonen had to go around Marcus Ericsson's Sauber into Turn 11 on his quick lap on ultrasofts, this suggest Ferrari had the pace to be quickest on Friday. Raikkonen himself suggested this was the case, which would actually make Ferrari favourite for pole.

It is interesting to note Hamilton, in a Mercedes that isn't the best at keeping the rear tyres in the temperature window, had a rear-end moment in the final corner on his quick lap. This hinted at the possibility of giving away a little grip on the rears at the end of the lap on relatively short-lived rubber that no driver was able to make a serious attempt at getting a second lap out of - and that several spun on.

It is also relevant that Raikkonen had the pace advantage in the first and last sectors, which are more dependent on speed on the straights than the twister middle sector. This suggests that, again, the Ferrari could be carrying less drag on the straights than the Mercedes, either by dint of having efficient downforce or running a little more trimmed out (most likely a mix of the two) - on top of having strong engine performance.

This could also be good news for Ferrari in a repeat of the late-race Bahrain GP situation, with one of its drivers being chased and without the need to make an on-track pass.

Overall, given that Ferrari traditionally doesn't look its strongest during Friday practice, this is extremely encouraging and sets the stage for a dramatic qualifying session.

The rest fitted in with the pattern we've seen through the season so far, with Red Bull a few tenths further back and not in the fight for pole position, and then a tight midfield pack. This time, that pack was led by Renault's Nico Hulkenberg ahead of the Haas of Kevin Magnussen.

Raw pace

1 Mercedes 1m33.482s (Hamilton)
2 Ferrari 1m33.489s (Raikkonen)
3 Red Bull 1m33.823s (Verstappen)
4 Renault 1m34.313s (Hulkenberg)
5 Haas 1m34.458s (Magnussen)
6 McLaren 1m34.632s (Alonso)
7 Force India 1m34.792s (Perez)
8 Toro Rosso 1m34.849s (Gasly)
9 Williams 1m35.340s (Sirotkin)
10 Sauber 1m35.624s (Ericsson)

"Ferrari I think are still quite quick, I think Red Bull actually were really quick on the long run," said Hamilton, who knows he's got a fight of his hands for pole position. "So it's good to see all the times so close."

"It's no secret that a few people are thinking of qualifying on the soft" Daniel Ricciardo

In itself, the Mercedes vs Ferrari battle sets up a tantalising qualifying session. But there's the added intrigue of the ultrasoft compound being something of a survival tyre for those who make Q3, obliged by the regulations to start on it thanks to using it in Q2, albeit not quite as dramatically as some feared it would be. Pirelli estimates the difference between the ultrasofts and the softs is 0.9 seconds, so although the gap to 11th in FP2 was 1.3s there could be some added peril there for those trying.

"It's no secret that a few people are thinking of qualifying on the soft, it's not that bad a tyre around here," said Ricciardo. "The ultra doesn't seem to last that long, so yeah, you might see a few yellow tyres in Q2."

Even tyre management expert Sergio Perez, in a Force India he might hope is just outside Q3 rather than in it for exactly that reason, accepts the ultrasofts could be all about survival. But there is the question mark over whether the anticipated higher temperatures for Sunday could help, as while the track temperature would be higher it would eliminate the graining that was a problem for some on Friday.

"They do drop a bit quicker," said Perez. "But Sunday we expect a change in track temperature, so we will see. That could probably make it worse."

As if to underline the point, Renault drivers Nico Hulkenberg and Carlos Sainz Jr started their ultrasoft long runs at near-frontrunning pace before dropping away dramatically. They were not an unusual case and, just as in this race in 2016, for those who do start on ultrasofts the first stint will be about going just long enough to make the strategy work before moving to softs and mediums.

Long-run pace is trickier to judge, partly thanks to the rain that arrived towards the end of FP2 and cut some runs short. There is a good body of long-runs on the ultrasoft tyre, but given the management requirements judging pace is a very dangerous game.

What does stand out is that, again, the Red Bulls seem to be extremely gentle in terms of thermal degradation (as do the Toro Rossos). While Mercedes was fastest on the below averages, based over five laps of the runs, Verstappen ran longer than any of the other frontrunners and was still lapping at a 1m39.113s on his 11th lap.

Long-run average pace*

1 Mercedes 1m38.971s (Hamilton)
2 Red Bull 1m39.057s (Verstappen)
3 Renault 1m39.289s (Hulkenberg)
4 Ferrari 1m39.490s (Vettel)
5 McLaren 1m39.613s (Alonso)
6 Force India 1m39.810s (Perez)
7 Haas 1m39.988s (Grosjean)
8 Toro Rosso 1m40.104s (Gasly)
9 Williams 1m40.894s (Stroll)

*no data for Sauber

Vettel's pace in the Ferrari also has to be heavily caveated, both because Raikkonen did not do a long run on the ultrasofts for comparison and because Vettel seemed to go aggressive on the tyres and suffered bigger degradation than others at the front of the field. But there is perhaps a hint of Ferrari's race pace not being so strong.

The big question is whether Red Bull was actually just too slow in reacting to the weather. Teams came into this weekend expecting the ultrasoft to be a nightmare, but Mercedes trackside engineering director Andrew Shovlin confirmed it shortened its ultrasoft runs because of rain.

The difference between the soft and medium doesn't seem that big on pace or degradation. That makes for as murky a picture as the polluted air around the circuit, which is extremely good news

"We had concerns over the ultrasoft coming into this event, but it was surprisingly consistent over the long runs and still going strong when we boxed both cars having see the rain approaching on the radar," said Shovlin.

Even so, all six of the Mercedes, Red Bull and Ferrari drivers could well get through Q2 using the softs and never have to go near the ultrasofts should they want to - assuming, that is, Ricciardo gets his single-lap act together after struggling to get the tyres working today. What remains likely is that, if some of any of the big three do end up starting on ultrasofts, and it's worth noting it's rare any of them do go for the slower tyre, Red Bull might be best equipped to handle them given its tyre management strengths. It might be no coincidence that sister team Toro Rosso also ran longer and faster than its single-lap pace suggests.

The late rain means the soft and medium compound data is sketchy. Hamilton, Ricciardo and Raikkonen all started long runs on the softs. That put Mercedes one tenth ahead of Red Bull, with Ferrari half a second off. Conversely, on the medium Pirellis, Vettel was a couple of tenths faster than Bottas - and both started faster than those on softs. Sadly, these runs were brief and curtailed, so offer nothing more than a vague pointer.

Last year's tyre of choice was the soft, which correlates to this year's medium - so the expectation is that will be a strong tyre. But the difference between the soft and the medium doesn't seem that big on pace and degradation even though the data is limited. Pirelli suggests a two-stop strategy could be fastest, even suggesting ultrasoft-ultrasoft-soft might be a workable option, despite the softest compound not lasting long when on heavy tanks.

That might look like a picture as murky as the polluted air around the circuit, which is extremely good news.

In qualifying, it might be a toss up between Mercedes and Ferrari - and even if one or the other prevails Red Bull could join the fight come Sunday. With the hope of strategic variation (there were eight different strategies across the top 10 finishers in Bahrain, for example), there's every reason to hope for the battle royale we've all been hoping for.

And with the possibility Ferrari might again be able to lock out the front row, then perhaps not have the outright fastest car on Sunday afternoon, it could make for a gripping race. As Hamilton mentioned today, Ferrari is the team that has been "flawless" so far this year, calling for Mercedes to bring it's A-game and Red Bull to show the pace it has hinted at in a race for the first time this year.

If all of this happens, the 2018 Chinese GP could go down as a classic. But, of course, this is just Friday. All the usual caveats apply.