Did Mercedes create its own controversy?

Three races into last year's Formula 1 world championship, Nico Rosberg and Lewis Hamilton fell out over the tactics each employed during their duel for victory in the Bahrain Grand Prix.

Hamilton won that race, but his Mercedes team-mate - who had dropped behind at the start - was unhappy at the way Hamilton had rebuffed his repeated attempts to repass for the lead. Conversely Hamilton was angered by the superior engine settings Rosberg had used to come back at him.

Three races into the 2015 season these two were at loggerheads again, as Rosberg complained Hamilton drove "unnecessarily" slowly to win the Chinese Grand Prix, and thus exposed Mercedes' second car to the threat of a resurgent Ferrari.

This post-race spat between last year's two principal title protagonists - the sort of personal tension that bolsters any great sporting rivalry - enlivened an otherwise processional grand prix at the front of the field.

Regardless of the pre-race warnings coming from the Mercedes garage, Ferrari was not as competitive here as it was in Malaysia, and Mercedes looked to have a big margin over the rest from the moment the cars first turned wheels on Friday.

But Sebastian Vettel's shock win at Sepang a fortnight prior had the Stuttgart/Brackley/Brixworth alliance rattled.

Ferrari's tyre management again had Mercedes rattled © XPB

Mercedes shouldn't have lost that race, given it began with the advantage of track position and two cars in the fight compared to Ferrari's one. But the Scuderia's superior tyre management over longer runs in the Malaysian heat helped it beat a team that has got used to running its own race at the front.

The champion team simply had to ensure there was no repeat in China. Theoretically, the Shanghai International Circuit shouldn't have presented anything like the same tyre-life conundrum to Mercedes as Sepang did.

The circuit layout switches the emphasis of tyre management from the rear of the car to the front, the conditions were much cooler than in Malaysia (helping to protect the rubber), and the upgraded W06 was further ahead on pace here.

Nevertheless, Mercedes entered the Chinese GP with a certain degree of paranoia about the challenge it might face from its new nearest rival, so it held pace in reserve on Sunday - principally because it feared the W06 would eat its Pirelli tyres too greedily again, and hand Ferrari another victory on a silver platter.

So Hamilton drove slowly. Fast enough to maintain a lead, but far slower than he could have driven had he wanted to.

The first stint (14 laps on a used set of softs) went off without a hitch, Hamilton reporting "these tyres have lasted really well" over team radio. He began his second stint (on new softs) lapping at a similar pace.

In the early stages of that second stint Rosberg grew impatient. "Get him to speed up!" he cried on the radio, with Vettel tracking less than two seconds behind.

The lead pack squeezed together during the middle stint © LAT

Mercedes explained to Hamilton that Rosberg was concerned he would destroy his own tyres faster if he got any closer, and asked the leader to up the ante (which Hamilton could do easily).

Hamilton suddenly began lapping in the 1m43s; Rosberg responded in kind; the Ferraris continued to match the Mercs (or lap fractionally faster).

By lap 25 Mercedes was warning Hamilton it would have to hand Rosberg the advantage of an earlier second stop if he didn't start going more quickly.

Hamilton upped his pace again (into the low 1m43s this time), but Rosberg couldn't match him, complaining: "my left front has become a problem". He was 1.8s behind on lap 25; then Hamilton pumped in the following sequence:

1m43.508s
1m43.647s
1m43.644s
1m43.239s
1m43.008s

The best Rosberg managed during that time was a 1m43.5s on lap 30, before making his second stop one lap later. The rest were 1m43.6-8s. As Rosberg pitted, Hamilton unleashed his withheld extra pace, pumped in two consecutive low 1m42s laps to protect his advantage, then made his own second stop on lap 33.

Verstappen's problem meant a safety car finish © XPB

For the rest of the race (with both cars running the slower medium tyre) Hamilton maintained a comfortable gap to his closest rival, which fluctuated only slightly. He had the lead out to 8.6s with three laps to go, before the safety car finish necessitated by the comically slow recovery of Max Verstappen's stranded Toro Rosso.

Throughout the first two stints of the race Hamilton was holding back, which allowed Vettel to stay close and made Rosberg very uncomfortable.

When asked whether he was aware Rosberg was getting backed up into the Ferrari, Hamilton replied: "I wasn't controlling his race, I was controlling my race. Going into the race we thought it would be a lot closer. We knew the Ferraris were very good with their long-run pace and also looking after their tyres, so today the real goal was to manage the tyres.

"My goal was to look after my car. I had no real threat from Nico so I just managed it. Generally, it was a much smoother weekend than we had in the last race. We had the full practice sessions, on my side of garage at least, and that made a real big difference to the balance of the car."

Rosberg responded by questioning the selfishness of Hamilton's tactics.

"It's interesting to hear from you Lewis that you were just thinking about yourself with the pace at the front," he said.

Hamilton raised his pace before the crucial pitstop © LAT

"Unnecessarily, that was compromising my race because driving slower than was maybe necessary at the beginning of stints meant Sebastian was very close to me, and it cost me a lot of race time as I had to cover him [strategically] and my tyres died at the end of the race because my [last] stint was so much longer.

"I'm unhappy about that. Other that that, there is not much to say."

Vettel did make his first two stops earlier than Rosberg, in a vain attempt to get the jump on the second Mercedes, but he was not really quick enough to threaten and ultimately fell away during the latter part of the race as a result. And, as Hamilton indicated afterwards, "if Nico wanted to get by he could try, but he didn't."

"It's not my job to look after Nico's race; my job is to bring the car home as healthy and fast as possible, and that is what I did," he continued. "I didn't do anything intentionally to slow any of the cars up.

"I'm out there driving as hard as I can, but within the constraints of the tyres. The team kept coming on the radio asking me to pick up the pace, but I'm trying to manage these tyres.

"It's like you have £100 and you have to spend it wisely over your stint. I was trying to make my stint go as long as possible. I was hopefully still wealthy at the end of it..."

It's easy to dismiss Rosberg's rant as the sour grapes of a driver who desperately needs to beat a rival who appears to have all bases covered at the moment. The question is whether Mercedes could have been more aggressive in this race and still protected itself from the Ferrari challenge, thus avoiding the situation that created fresh tension between its two drivers.

Team chief Toto Wolff ultimately felt it wasn't a risk worth taking. "We thought we might run into trouble with the option [soft tyre] and then we found out it was actually holding on much better than expected, and much better than Ferrari," he explained.

Wolff has another Mercedes driver dispute to deal with © LAT

"With Malaysia still being in the back of our mind, we decided to change the car in various aspects to make it last on the tyres. We didn't know when the point was coming or how sudden the drop would be if the tyre would go over the cliff; this is why it was learning by doing at that stage.

"We wanted to cover Ferrari with the option, so we put the option on [at the first stop]. Lewis needed to take the option longer than expected, so he was controlling his pace - from his point of view, completely understandable.

"Nico was really running into trouble; he was bunched up behind Lewis, he couldn't go anywhere near, so he asked for a two-second gap to Lewis to protect the tyres a bit, which he did, and at the same time Sebastian was increasing the pace behind him. So it was understandable between both of them."

Wolff dismissed any suggestion that Hamilton was deliberately trying to back Rosberg into the Ferrari drivers "in order to make him finish third or worse" and argued Mercedes had intervened as far as it could in asking Hamilton to up his pace when it did - given its policy of equality between the drivers and not splitting strategies under ordinary circumstances.

Hamilton can argue (as he did) that Rosberg should simply have driven faster; Rosberg can argue Hamilton could have gone faster than he did while still protecting the team's one-two result from Ferrari's eager clutches.

Mercedes is caught in the delicate balancing act of looking after its collective interest, managing the ruthless individual hunger that is a prerequisite for elite racing drivers, and allowing them to race freely.

As three-time world champion and Mercedes non-executive chairman Niki Lauda explained after the race: "Sure, he [Hamilton] will drive selfish. These guys...I call them egocentric bastards, let's say, and this is the only way to win a championship. It's the oldest thing.

Vettel's pace is causing problems for Mercedes © LAT

"Nico tried hard all the way, you could see this from his laptimes. He had Vettel behind, which was a worry at some stage, and he had to fight hard, hard, hard to catch up to Lewis and beat him, but Lewis was better in the end.

"Sure, it hurts. When I was being beaten by [Alain] Prost all the time in the old days I was not happy. On the other hand, Nico is a guy who comes back quickly, so thank God there is only one week to the next race so the bullshit will stop quickly when they start driving again."

Whatever tensions needed defusing afterwards, Mercedes ultimately achieved the right result in this race, and it's easy to say with hindsight that it should have taken a different tack and run its race faster simply to avoid uncomfortable conversations.

Mercedes was clearly genuinely concerned that if it went too quickly it risked losing out to Ferrari. This was based on the fact Kimi Raikkonen had been only fractionally slower over long runs on the medium tyre in practice, but gone on for longer.

In addition, Mercedes feared it couldn't make the soft tyre last long enough to complete the race on two stops, so was actually considering using the unfancied medium twice during the race. Pirelli predicted two soft-tyre stints for everyone and Mercedes' own soft-tyre Friday runs were comfortably faster than Ferrari's, but with some concerning 'drop-off' towards the end of the run.

"If we are not driven by scepticism about our own performance and always expecting the worse from our main competitor, you will always lose out at one stage and Malaysia might happen again," argued Wolff.

"So in everything we do in how we tackle the race, it was always expecting surprise pace [from Ferrari]. This is why there is no such thing as being over-cautious. If you go into a race weekend over-confident, with such an over-confidence you can get caught out."

Ultimately, the hindsight of Malaysia engendered a necessary degree of caution on the Mercedes pitwall, which in turn led to a closer race than might otherwise have been with Ferrari, which led to a tense situation between its drivers that normally could have been avoided.

But that's not Hamilton's problem. His job was to do what the late-great Juan Manuel Fangio always said was the aim: win the race at the slowest possible speed. Hamilton did that. What Rosberg needs to do is find a way to beat a driver who is absolutely on top of his game right now.