Mercedes' warning shot shows how hard it will be to dethrone

After a second half of the season full of twists, turns and plot twists, it was appropriate Lewis Hamilton and Mercedes rounded out the 2019 Formula 1 campaign by returning to dominant form in the Abu Dhabi finale.

To underline his advantage, Hamilton even nailed fastest lap with two laps remaining on well-worn hard Pirellis. This was a crushing, emphatic full stop to a season in which driver and team again demonstrated their supremacy, even when others were capable of going quicker.

That Ferrari's fuel use was catapulted back to front and centre by the pre-race bombshell that F1 technical delegate Jo Bauer had referred it to the stewards was also appropriate in a season blighted by suspicions over its engine advantage. This was because the FIA had discovered a "significant difference" between Ferrari's declaration of how much fuel there was in the car - a requirement since a lengthy technical directive was issued in February requiring teams do this and the means by which it would be measured - and the real amount in Charles Leclerc's Ferrari. The team was later fined €50,000 for under-declaring the fuel mass by 4.88kg - potentially 4.4% more energy on board relative to the 110kg in-race fuel limit.

While Hamilton assured the team over the radio after the chequered flag that he genuinely had broken a sweat, it was more Sunday drive than pitched battle. A good start ensured the lead was banked in the early seconds of the race and he finished the first lap 1.7 seconds clear of Leclerc.

The Ferrari driver, who started third behind Max Verstappen, used superior traction off the Turn 7 hairpin leading onto the first back straight and was clear of the Red Bull by the time they got to Turn 8. Verstappen then came under pressure from Sebastian Vettel, holding him off into Turn 11 to keep hold of third place.

Hamilton pulled away at almost half a second per lap to be just under six seconds clear after 10 laps. It was already clear there was no stopping the lead Mercedes and the chasing Ferrari was far more interested in trying to hold on to a second place that could give Leclerc third in the drivers' championship. Fearing an undercut attack from Verstappen, Ferrari called Leclerc in after just 12 laps despite him starting the race on mediums.

By the time he peeled into the pitlane, Leclerc was less than two seconds clear of Verstappen. Red Bull, wisely, decided to leave Verstappen out to gain a tyre-life offset given he had no chance of jumping Leclerc. But to complicate matters, Ferrari decided to double-stack its drivers with Vettel coming in to switch from soft tyres to hards at the same time.

Vettel was a good seven and a half seconds behind, so there was plenty of time for this manoeuvre. But both the front and rear changes on the left side were problematic and Vettel was parked for almost seven seconds - the left-rear proving to be the bigger delay. Fortunately, he'd built an advantage of just under five seconds over fifth-placed Alex Albon, so when the Red Bull driver responded and pitted a lap later after a rapid in-lap, also taking hards, Vettel was still ahead - just.

This left Hamilton leading from Verstappen, with the Red Bull driver going to lap 25 before stopping to take hards. A lap later, Hamilton bolted on his hards for the run to the finish and never lost the lead. This ensured he was on for a rare 'grand slam' of pole position, fastest lap and all laps led - the sixth of his career.

Bottas stopped to take hards at the end of lap 29, emerging in sixth. The chase was on and, by lap 38, Bottas was all over Albon for fourth - at which point the race took a surprising turn

Despite Leclerc's lengthy undercut, Hamilton emerged with an advantage of 6.3s, which he extended to 13s by the end of lap 31. By this time, Leclerc was hanging onto second by the skin of his teeth from Verstappen, who was using his 13-lap tyre advantage to good effect. Five seconds behind Leclerc after his stop, he quickly reeled the Ferrari in despite complaining over the radio about the 'handbrake effect' caused by power delivery problems that showed early in the race but became a bigger problem after the pitstop. It meant the car wasn't behaving the way he wanted it to and this was put down to a system problem on the Honda side.

"Torque holes and throttle," said Verstappen when asked to explain his problem. "There were some delays so it was not great, and we couldn't fix it so we drove around the problem. When I got on the throttle, it was not doing what I want. It did cost me lap time, but it wouldn't have given me the win."

Second place was a different matter. As Leclerc and Verstappen closed on the lapped Williams of George Russell on the first back straight on lap 32, the Red Bull driver made his move and dived up the inside on the brakes into Turn 8. Leclerc emerged from the left/right well behind, but a combination of the DRS and the Ferrari unleashing its full power allowed him to close on Verstappen and attack to the outside of Turn 11. Verstappen held him off through the corner, then took off with second place in his pocket.

Behind, there was an intriguing battle for fourth place. Vettel held a three-second advantage over Albon, but the second Mercedes of Valtteri Bottas was looking ever-more threatening having started from the back of the grid.

Bottas went into the weekend knowing he would start at the back thanks to the failure that put him out of the Brazilian Grand Prix, although he attacked qualifying normally and was second fastest. With a fresh engine, his second of the weekend after suffering a pneumatic leak during FP2, he had licence to go on the attack.

He jumped the two Williams drivers by the first corner, then initially passed Romain Grosjean's Haas for 17th into the Turn 5/6 chicane. Boxed in by Pierre Gasly's Toro Rosso at the Turn 7 hairpin, Bottas was repassed around the outside before dispatching them both on the run into Turn 8. That added up to 15th by the end of the first lap.

He then picked off Kimi Raikkonen, Lance Stroll, Antonio Giovinazzi, Kevin Magnussen and, on lap 12, Sergio Perez. His task was made more difficult by the fact the DRS was unavailable until lap 18 as a result of a server problem. By that time, thanks to others stopping, Bottas had climbed to fifth, immediately using the DRS to pass soft-shod Nico Hulkenberg, who ran an extended first stint ahead of an ill-starred switch to mediums for the run to the finish.

By the time he passed Hulkenberg, midway round lap 18, Bottas was 49s off the lead but within 20s of Leclerc. Vettel and Albon were running together two seconds behind the Mercedes. But Bottas's pace over the next 10 laps was formidable and he was able to chip away at Leclerc by almost two tenths per lap and drop Vettel by the same margin. This raised hopes for a possible run at the podium.

He eventually stopped to take hard tyres at the end of lap 29, emerging in sixth place. Vettel, in fourth, was 16.5s up the road, with Albon 3.4s behind the Ferrari. The chase was on and, by lap 38, Bottas was all over Albon for fourth. At which point the race took a surprising turn.

That Leclerc peeled into the pits at the end of lap 38 while running a lonely third was no surprise. He had a fresh set of softs and the space to stop without losing position for a tilt at the fastest lap point - and although giving away time, this strategy would maximise his chances of retaining third from Bottas. But Ferrari again pitted Vettel on the same lap, successfully this time, to take fresh mediums. In doing so he relinquished places to Bottas and Albon, who swapped positions on lap 39, the Mercedes driver making an easy move into Turn 8.

Vettel never had a hope of either holding off Bottas or catching him, so the key was to close the 21s gap to Albon in the remaining 17 laps. He cut it fine and it wasn't until lap 53 of 55 that he made his move, pulling past Albon on the run to Turn 8. But Albon wasn't in any mood to give up and dived back up the inside. Vettel checked up and let him go, but made the pass again on the following straight. Over the radio, he complained about Albon's late move as being "borderline", but the Red Bull driver gave that short-shrift when it was put to him after the race - "it's racing," was his verdict.

Had the battle in the midfield been the one for overall victory, this would have gone down as an all-time classic as it built to a thrilling last-lap denouement

Bottas still had aspirations of a podium finish, but fell just a second short despite pressuring Leclerc at the end. Perhaps he had good reason to rue the fact he took a little longer than he would have done clearing traffic thanks to the early lack of the DRS, which potentially cost him as much as six seconds. But this was still a decent performance to sign off from a strong season. He might also have had the consolation of a bonus point for fastest lap, but for Hamilton pulling the final rabbit of the season from a hat.

Hamilton was happy with the way the hard Pirellis were standing up, particularly given he could take a cautious approach during the second stint given the gap to Verstappen. So with three laps remaining, he had a go and banged in a 1m39.283s - 0.432s quicker than what Bottas had managed 22 laps earlier on the second lap of a hard stint. Hamilton had the advantage of significantly less fuel, but also tyres that already had 26 laps on the clock when he went for it.

"The hard tyre is quite resilient, it goes a long, long way," said Hamilton. "Towards the end of the race I was like, 'I've got to push and see if I can extract any more performance from the car'. I do wish that we had some battles, I saw on TV you guys [Leclerc and Verstappen] battling."

Had the battle in the midfield been the one for overall victory, this would have gone down as an all-time classic as it built to a thrilling last-lap denouement. McLaren started the race ahead, with the Renaults close behind. Lando Norris, who started at the head of the group in sixth, had control for almost the entire race.

Initially, he headed Carlos Sainz Jr, with Daniel Ricciardo and Hulkenberg chasing. But a huge right-front lockup into the Turn 17 right-hander forced him to pit immediately, and too early, at the end of lap eight. That dropped him firmly into traffic and, while he battled his way through (sans DRS), Sainz took up leadership of the group.

With Binotto admitting Ferrari has much to do and Red Bull looking back on another year of sniping for wins here and there, the race was a reminder of what makes the Mercedes-Hamilton combination so special

Ricciardo was the next to stop, attempting to undercut his way past Sainz by pitting on lap 11. Sainz, inevitably, responded a lap later but couldn't cover the move and dropped behind Ricciardo. After initially passing Ricciardo into Turn 5, but running across the chicane and having to give the position back, he reclaimed the place for good two laps later with a brilliant late dive up the inside of the Renault into Turn 8 - coming from a long way back. It was a move worthy of Ricciardo himself.

But all three had lost more than they would have done thanks to the lack of DRS, with Norris leading the trio bottled up behind Grosjean, which helped to bring others into play. Hulkenberg stopped for mediums at the end of lap 18 after starting on softs and emerged between Sainz and Ricciardo.

Perez, meanwhile, revelled in his marathon stint on mediums on a track where his mastery of mitigating tyre slip was a huge boost. He didn't stop until lap 37, which allowed him to switch to hards with a mighty offset over those ahead. Daniil Kvyat went even further, to lap 40, having started on hards, to switch to mediums - although time lost behind Raikkonen early in the race when the DRS was not available meant he had more work to do than he might have done.

Perez rejoined 12th, 3.5s behind Ricciardo but the group of McLarens and Renaults all within 8.5s. He used his 26-lap tyre advantage to dispatch Ricciardo for 11th - who then dived into the pits to take on softs, with Sainz then aborting his planned one-stopper to take mediums. With Kvyat having pitted from seventh place and rejoined at the back of the group, this put Perez ninth.

He then overtook Hulkenberg, who by now was struggling on well-used mediums, and set about Norris. Norris's early stop meant he was on hards with over 40 laps on the clock and was given the instruction that he had nothing to lose and to go for it. He set some impressive lap times given the grip, which meant Perez had to work for it. It seemed Norris had done just enough to make sure of midfield 'victory', only for Perez to come from a long way back on the outside on the approach to Turn 11 on the final lap - the last realistic passing opportunity.

Perez went around the outside to bag a brilliant seventh, leaving Norris dejected. While Perez praised Norris for how fair he had been, the dejected McLaren driver publicly flogged himself after the race for not being more aggressive and denounced himself as "too polite".

Behind, Kvyat climbed to ninth in those frantic final laps - compromised by some minor front wing damage that he appeared to suffer without contact after pulling out of Ricciardo's slipstream. Sainz, meanwhile, also left it late before pulling off a brilliant late swoop to the inside at Turn 11 to pass Hulkenberg - who subsequently fell behind Ricciardo - for 10th place. This was a crucial move as it handed the delighted Sainz sixth in the drivers' championship.

Much as Hamilton might have desired a similar path to outright victory, the reality was he had everything utterly under control for his 84th win. With Ferrari team principal Mattia Binotto admitting after the race his team has much to do and Red Bull looking back on yet another season of sniping for victories here and there, it's a reminder of just what makes this team and driver combination so special - and what it will take to topple them.