The soul-searching that led to Ferrari's drastic turnaround

You'd have got pretty long odds on Ferrari getting a one-two in Singapore.

While the team had enjoyed irrepressible form at Spa and Monza, the Marina Bay circuit is incredibly far removed from those two venues. So, when Sebastian Vettel crossed the line to win his first race in over a year, with Charles Leclerc in tow, it seemed to represent an overnight turnaround in performance.

But in reality, the story goes much deeper than that.

At the start of the year, testing form meant that big things were expected of Ferrari. But experience demonstrated that the SF90's performance envelope was too heavily biased towards straightline performance at the expense of downforce.

Since this imbalance was intrinsic to the complete car concept, resolving it has taken months of detailed work - including a few wrong turns. But Ferrari now appears to present a very genuine threat to Mercedes' might for the rest of the year.

Ferrari brought a plethora of upgrades for Singapore, most notably a new nosecone design that featured a pair of nostrils. Those feed airflow into a 'cape', a flowing bodywork appendage (previous version inset below) added to the nose to build up more front-end downforce and subsequently feed the bargeboards with stronger flow structures.

That, combined with a new floor featuring banks of fins to assist the longitudinal cut-outs along the edge while drawing airflow outwards, is giving the new diffuser a much more concentrated supply of clean air to balance out the rear downforce. A new rear wing completed the package, indicating that Ferrari has conducted a top-to-tail overhaul of its aerodynamics.

On the face of it, those changes contributed to Ferrari's sudden upswing on a circuit where it should have struggled. Even before the weekend, Vettel and Leclerc weren't particularly hopeful of a good result.

But in truth, the duo's mastery of Singapore is the culmination of work that was set in motion months ago, when the low-drag design philosophy was failing to yield results at the start of the year.

Even as the calendar drew towards the enforced summer shutdown, Ferrari was working away at making a successful turnaround

Ferrari looked particularly good in Bahrain and Canada and, to a lesser degree, Baku. But the chronic lack of pace at the lower-speed venues suggested a serious deficiency in downforce - particularly at the front end, where the drivers struggled to get the right steering response.

Early on, Ferrari began an internal review of this year's design philosophy, and brought a number of new parts to the French Grand Prix with the intent of guiding the car along a new development path. There, it gave its characteristic front wing a slight redesign, partnering it with a new floor, featuring three banks of fins to direct airflow outwards. Ultimately the preliminary running at Paul Ricard yielded mixed results.

The front wing stayed but the floor was taken off, the latter presumably requiring a longer gestation period in the factory as the team continued to understand how it worked. Those fins were almost identical to a design that Ferrari ran in various practice sessions last year, starting at Suzuka, but never made it to a race. While most would give up on a design that provided such opaque results, Ferrari's perseverance suggested that there were genuine benefits to it, as long as the engineers could make it work on track.

But Ferrari was sufficiently buoyed by the front wing upgrade, and continued to develop around it. Since then it has been steadily adding new developments to the car, drawing on ideas from its rivals but adapting them to suit its own package. Like Mercedes, it embarked upon a marginal gains approach, but needed each new piece of kit to deliver a larger chunk of lap time if it was to have any hope of staging a comeback.

Low-speed, high-downforce woes persisted before the summer break, and Ferrari was clearly the third-best team at the Hungaroring, as Mercedes and Red Bull duked it out for honours. But even as the calendar drew towards the enforced summer shutdown, Ferrari had been working away at making a successful turnaround.

Spa and Monza's low-downforce characteristics were always going to suit Ferrari, but they were crucial races and instilled a renewed feeling of confidence within the engineers and personnel at Maranello. Leclerc, sealing two victories on the bounce, had proved his mettle in a winning car, while Vettel had to pick himself up after a humbling Italian Grand Prix. Singapore, however, would be the litmus test of the team's technical progress.

Even after Friday practice, most expected the battle for victory to be between Lewis Hamilton and Max Verstappen. Vettel and Leclerc performed back-to-back tests initially in first practice, with Vettel running the old-spec parts and Leclerc the new ones. During the session, the two swapped specifications, and looked set to continue doing that until Leclerc's gearbox became wedged in fourth gear.

It was up to Vettel to continue with the new parts, and everything seemed to click. A year ago, Ferrari brought a major upgrade package to Singapore that ultimately didn't deliver the anticipated gains and was blamed for a late-season loss of form. Ferrari's more discerning approach this season suggested this might not be repeated, but Friday's running still brought few clues as to what would transpire, as Verstappen and Bottas headed the opening two sessions.

But there was one hint in the Ferrari's sheer poise over the many kerbs and bumps on the Singapore streets. Watching Leclerc gently coax his scarlet chariot around the corners without hacking away at the steering wheel suggested there was more speed to come.

Then, when the Monegasque driver topped practice on Saturday morning, a Ferrari resurgence suddenly looked very real. Our own Edd Straw, who cast his keen eye over the session's proceedings from trackside, was effusive about Leclerc's graceful trajectory though the challenging Turn 5 - the right-hander that leads onto the fast straight in the track's first sector.

Edd Straw's trackside analysis

When Charles Leclerc approached Turn 5 on his best lap in FP3, he and Ferrari weren't considered a threat in Singapore. By the time he'd gunned it down the straight, it was clear Ferrari had taken a step forward that might make it a genuine pole contender. And so it proved.

While Ferrari's most significant advantage was on the long, flat-out section down to Turn 7 in the first sector, the SF90 was better than expected in the corners. On his push lap, Leclerc carried in hugely impressive speed - to the point where you'd expect one end of the car or the other to slide. But it stuck. The Ferrari was already riding the bumps more effortlessly than its rivals, but to carry that speed into, through and (crucially for lap time) out of the corner transformed that perspective.

In qualifying, Leclerc surged to pole despite a messy lap and the Ferrari was clearly brimming with outright pace

This is a car that has often looked a little reluctant on turn-in to slower corners in particular, but here Leclerc was able to get on the brakes and get the car rotated without hesitation. It looked planted in a way that hasn't always been the case this year and that's what really caught the eye. That doesn't necessarily mean it's better in this type of corner than Mercedes or Red Bull, but you get used to car characteristics and it was the Ferrari that looked, in that moment, very different.

We've yet to see how the car will respond in longer corners, but Turn 5 isn't as short as many on the Singapore circuit so it hints that, just maybe, this step will continue to benefit Ferrari on the upcoming run of tracks where it previously wasn't expected to be a contender. The only caveat to add is whether the Ferrari was absorbing the bumps so well that it benefitted more than Mercedes in the bumpy braking zone compared with the rest. Ultra-smooth Sochi, this coming weekend, should answer that question.

In qualifying, Leclerc surged to pole despite a messy lap, which surprised all and sundry, and the Ferrari was clearly brimming with outright pace.

Although Leclerc was aggrieved by Ferrari's race strategy, which relegated him to second, his hopes of winning a third race in a row were ultimately collateral in delivering Ferrari a one-two finish.

Even in race trim, the Ferraris continued their shock steamrolling of the Singapore weekend, managing pace in the initial laps before opening the taps once in clear air and free of traffic.

While the aerodynamic changes to the car will have provided the drivers with bags of confidence during turn-in, Ferrari also seems to have put its suspension kinematics together in a window that was perfect for the demands of Singapore. While Mercedes ran its car a little more stiffly sprung, Ferrari was able to absorb the physical challenge of the bumps and kerbs with consummate ease, offering its drivers a nice, smooth ride.

Sochi will be a greater equaliser; devoid of bumps and with asphalt smoother than a snooker table, the circuit shouldn't be as much of a challenge in braking zones.

It's also a circuit at which Mercedes holds the monopoly on victories, winning the five Russian races that have been held. It's tailor-made to be the ultimate test of Ferrari's progress this season, and while the full-throttle sweepers will play into the power-laden SF90's hands, its Singapore performance must translate to Sochi's point-and-squirt corners if the applecart is to remain upset.

If Ferrari turns up in Russia and shows any signs of a repeat, then the remaining races offer the tantalising prospect of a strong end-of-season run. Suzuka's mix of corners and elevation render it one of the most technical circuits on the calendar, while Mexico's low air density means that the highest-downforce package is needed. Races at Austin and Sao Paulo are technical too, while the two long straights at Abu Dhabi can play neatly into Ferrari's hands.

But Mercedes has the resources and the knowhow to turn its post-summer form around. An unexpected defeat in Singapore will make its thousand-strong personnel hungry to fight back, and its advantage in both championships is still incredibly healthy. But if Ferrari can continue to produce results at venues that haven't suited its car this season, then it'll be a colossal warning shot across Mercedes's pristine bow. And that's when things can become rather interesting.