The chronic weaknesses that decided the Brazilian GP

A Mercedes driver should have won the Brazilian Grand Prix. Both were fast enough. The faster of them almost managed it despite starting from the pits! The other should have got the job done having started from pole position. But both failed ultimately, to the delight of Ferrari and Sebastian Vettel.

A chronic weakness of the Mercedes Formula 1 car played a part in scuppering star man Lewis Hamilton's chances, despite a stunning recovery drive from that pitlane start, while team-mate Valtteri Bottas paid the price for a long-standing flaw in his competitive make-up, which undid his hopes of a better result once again at the crucial moment.

Bottas is a very talented driver and a hard worker to boot, someone who reviews the details of every race methodically and always tries to learn and improve.

That diligent approach has helped dig him out of a competitive slump since the August break, which dropped him out of title contention and made him look a shadow of the driver that won two of the first nine races.

After qualifying fractionally behind Hamilton at Mexico City, Bottas was fast in every session at Interlagos, and beat Vettel's Ferrari to pole after Hamilton's uncharacteristic crash took one Mercedes out of the fight on the first flying lap of qualifying.

But when Bottas sits down to review the Brazilian GP, he will surely regret that he did not do more to fend off Vettel's successful challenge at the start of the race.

The aggressive decisiveness displayed so regularly by Verstappen and Ricciardo further highlights Bottas's shortcomings

Firstly, he could have done with making a better initial getaway. Bottas lost traction as the cars accelerated through the gears on the short run to the Senna S, which made him vulnerable to attack.

"The issue was the initial wheelspin," explained Bottas. "As soon as I started to release the clutch I broke the traction. I had wheelspin and a poor getaway.

"I was trying to cover the inside, but looking in the mirror I couldn't see Seb anywhere. I was guessing he would come inside, and he did."

Vettel used his superior traction to edge alongside as they approached the first left-hander, but his own start wasn't perfect and he only had his Ferrari partly alongside as they braked for the turn.

"Initially I had a very good launch and I thought 'I got this', then I was maybe a bit too greedy spinning up the wheels a little bit, losing some momentum on Valtteri," Vettel said.

"I looked over and saw he was still struggling and gained a bit on the second phase to get momentum into first corner.

"I knew I had to go for it - there was a little bit of a gap and I went for it. It was important."

Bottas elected not to brave it with Vettel and hold on around the outside through Turn 1, which would have given the Mercedes the inside line for the second part of the S and a chance to fight back.

Instead, Bottas conceded position and slotted into second place, a decision that effectively settled the race in Vettel's favour.

"With a good start it would have been possible to keep the lead because our pace was pretty similar," Bottas added. "Being first out of Turn 1/2 would have been quite a different race. But if and if..."

During his fine formative seasons with Williams, a tendency to be overly tentative on the first laps of races was the chief weakness that stood out for Bottas.

He even admitted at the end of last year that it was an area in which he could "definitely still improve", in terms of finding the right balance between attack and defence at that most crucial phase of races.

This season has been a mixed bag again in this regard. He nailed it - with help from a tow and long run to the first corner - to beat both Ferraris to victory in Russia, and did well again (a little too well many rivals felt) off the startline to win in Austria.

But in Spain he was caught in two minds under pressure at Turn 1 and ended up in a three-way collision with Kimi Raikkonen and Max Verstappen, and was fortunate to get away with more contact with Raikkonen at Turn 2 in Azerbaijan, having left his nose in trying to defend position.

The aggressive decisiveness displayed so regularly by Red Bull drivers Verstappen and Daniel Ricciardo in such circumstances further highlights the shortcomings Bottas still has in this regard. He can still be considered a slightly soft touch in wheel-to-wheel battle. You can bet both Verstappen and Ricciardo would have toughed it out with Vettel through Turns 1 and 2 had they been in Bottas's shoes.

Mercedes team boss Toto Wolff admitted Bottas still lacks a bit of "killer" instinct compared to his "rock and roll" team-mate Hamilton.

"Valtteri had a solid race," was Wolff's verdict. "He lost it at the start. The initial getaway was good, but there was too much wheelspin through the gears.

"He's not very happy about the performance. He's not satisfied, because it was difficult for him to shine. He needs to recover in Abu Dhabi and start fresh next season."

The race at the front descended into stalemate after the initial battle between Bottas and Vettel. Bottas was only three hundredths per lap slower on average than Vettel over the 20 laps of proper racing they did through the first stint on the super-soft tyre, and only four hundredths per lap slower on average over the 42 comparable laps they each managed on the soft compound in the second half of the race.

The pitstop phase at the end of the first stint presented Bottas with his only other realistic chance of denying Vettel victory. Mercedes attempted to jump the Ferrari by calling Bottas in before Ferrari had a chance to service Vettel first, at the end of lap 27 of 71.

Bottas got close as the Ferrari emerged from its own reactive pitstop at the end of the following lap, but Vettel crucially made it into the Descida do Lago still ahead as they finished the first sector of lap 29.

"Our undercut was a little move of desperation," said Wolff. "We knew we lacked half a second, but nevertheless we gave it a go and the result was as expected."

It's possible Bottas might have challenged Vettel into Descida do Lago, had the first sector of Bottas's out-lap not been half a second slower than Vettel's. Bottas went fastest of all through the middle sector of his out-lap - four tenths quicker than Vettel managed - and did a personal best in the third, but he paid for Mercedes' stop being 0.6s slower than Ferrari's.

"Pace-wise it was very, very close," reckoned Bottas. "We were trying to put a lot of pressure on Seb, especially in the pitstop, but it was not quite enough. I got close after he came out of the pits, just not quite enough to try to overtake.

"I'm definitely disappointed after a good day yesterday, and it's obviously not so good for me in the battle for second place in the championship.

"We need some miracles in Abu Dhabi."

Third placed Raikkonen wasn't fast enough on a "tricky" set of super-soft tyres through the first half of the race to pose any real threat to the top two, slipping more than four seconds behind Bottas and out of contention before the pitstops, while Verstappen burned his tyres up in vain pursuit of the second Ferrari, unable to perform miracles in the face of a half-second engine deficit, exacerbated by the need to run the Renault turbo at reduced speed to protect reliability.

So, it fell to last-starter Hamilton to attempt a miracle of his own in hope of somehow denying Vettel victory.

After crashing out of qualifying spectacularly on Saturday, Hamilton said he headed into Sunday's race focused only on "redeeming myself". He certainly managed that, making full use (for the first time this year, he claimed) of the fresh engine Mercedes fitted to his car overnight to recover to fourth, finishing less than 5.5s shy of victory.

"For me it was the best fourth place I've ever seen!" enthused Wolff. "If you consider starting from the pitlane and ending up 5.4s behind the leader, it's quite an astonishing drive."

First-lap incidents that eliminated Stoffel Vandoorne, Kevin Magnussen and Esteban Ocon, as well as severely delaying Ricciardo, Pascal Wehrlein and Romain Grosjean, helped Hamilton quickly up to 14th by the end of the second lap, and when racing got under way properly at the end of lap five, after a safety car period to clean up the mess, Hamilton made short work of passing Brendon Hartley, Lance Stroll, Marcus Ericsson, Pierre Gasly and Carlos Sainz Jr.

It took a bit longer to clear Nico Hulkenberg's Renault, Sergio Perez's Force India (which put up a spirited if futile defence) and the race-long Felipe Massa/Fernando Alonso duel, but by the time Hamilton reached the Descida do Lago on lap 21, he was up to fifth, trailing Vettel by a little over 17s, with a little under 50 laps to run.

"It was the best fourth place I've ever seen" Toto Wolff

Having started on the soft tyre and run a longer first stint than the leaders, Hamilton made his own stop at the end of lap 43 and fitted the faster super-soft tyre. Hamilton now had 28 laps to charge for victory.

At times, he was lapping a second faster than the leaders. He cleared Verstappen's hobbled Red Bull without too much difficulty to move up to fourth with fewer than 12 laps to go, but Hamilton came unstuck when he reached the back of Raikkonen's Ferrari in the closing stages.

Hamilton felt he was quickest by a "long way" in this race, and probably would have won easily had he started on pole. His pace on the soft tyre was prodigious all weekend, but his hopes of a podium, or even a sensational victory, were thwarted in part by the Mercedes W08's weakness in traffic.

Hamilton lost crucial time stuck behind slower cars, such as Stroll's Williams, during lappery - regularly understeering wide through corners as he made his way through. Hamilton then struggled to follow Raikkonen's Ferrari at the end as the Mercedes' super-soft tyres gave up the ghost.

If the W08 had the SF70H's capacity for following other cars without damaging the tyres so badly, perhaps Hamilton could have achieved more. Had Bottas got as close to Vettel as Hamilton got to Raikkonen, perhaps he could have achieved more too.

Jacques Villeneuve called Bottas's performance "embarrassing" when judged against Hamilton's remarkable charge. That's perhaps a bit harsh, but certainly Hamilton's star show put Bottas very much in the shade.

"When we discussed it in the morning, what we deemed a realistic target [for Lewis] without the safety car was P4," reckoned Wolff. "We had the safety car, so that helped us a little bit, but the [pace] gap to the Ferraris was too close to have really achieved much more.

"I think a win would have been possible; Lewis was the quickest guy out there, but you must also consider that Sebastian was managing the pace at every time of the race but the last laps, so we haven't probably seen a real race."

Vettel claimed he'd been pushing "flat out all the way" on the podium, and later suggested Hamilton was no real threat, instead benefiting from that alternative tyre strategy being better suited to Sunday's super-hot track conditions. Vettel also argued Bottas had help from a race-long tow, while Vettel's Ferrari suffered for a lack of straightline speed.

"If you are fair, we are losing on the straights and that was enhanced with the tow - we were half a second quicker in the middle sector but losing it on the straights," Vettel said.

"It was very close. It's not the first time this year that a mirrored strategy has some advantages. It is not attractive starting in front, but can be attractive starting from where he [Hamilton] has. The track ramped up at the end, so the super-soft was the faster tyre."

Ultimately, it would have been a real shock had Hamilton - who thought he'd finish "somewhere around fifth or sixth" before the start - somehow stormed through from the pitlane to win this race, and we'll never know how much, if any, pace Vettel held in reserve in case Hamilton somehow made it up to second.

The Mercedes driver who lost the most realistic chance of winning the Brazilian GP was Bottas, who has clearly improved markedly of late, but still has plenty of work to do to overcome his residual weaknesses and become a true match for the very best drivers on the current grid.