Lewis Hamilton crushed Nico Rosberg for much of the first half of the year, but over the final six races it was clear his team mate had become a much greater threat.
Did Hamilton back off once the championship was won, or did Rosberg find a way to access more performance from the W06 than Hamilton could access? The latter view seems more persuasive, though that?s not to say the former would merit him being ranked one place higher.
Hamilton began his championship defence in superb form. The foundation stone of his success was a turnaround in qualifying compared to last year, clinching pole position in 11 of the first 12 races. This virtually guaranteed Rosberg never got a look-in.
But tellingly, during this time Hamilton never managed to win more than two races in a row. Victories slipped through his fingers due to tactical errors in Malaysia and Monaco ? the latter of which he had a share in the responsibility for ? and the odd occasion when Rosberg snuck ahead, as in Spain and Austria.
Hamilton went into the summer break anxious to put a poor showing in Hungary behind him. He?d piled error upon error in what was by far his worst race of the year, but bounced back with wins at Spa and Monza.
Ironically it was only once Rosberg started regularly knocking him back to second on the grid that Hamilton managed to take a trio of consecutive wins. Adversity often brings out the best in Hamilton, and in Japan and the USA he dealt with his team mate ruthlessly at the start, setting him up for wins.
In between the two he picked up a fortunate victory in Russia when Rosberg was sidelined with a throttle problem. The distribution of technical problems fell less evenly at Mercedes than it did last year, which contributed to the championship being concluded earlier than it might have been.
Having beaten Rosberg 12-1 in qualifying over the first 13 races, Hamilton lost 6-0 over the final half-dozen. Although Hamilton himself has admitted his motivation waned once the title was won, it?s hard to accept the idea that he began ?phoning it in? well before then. Strikingly, this period closely coincides with the post-Spa restrictions on tyre pressures: the only time Hamilton was on pole after then was at Monza, where Rosberg was unable to run Mercedes? upgraded engine.
Once Rosberg wised up to the fact that he had to keep Hamilton behind him at the start to convert poles into wins, the last three races all fell to him. Was Hamilton still giving his all? His relentless search for strategic alternatives, and his decision to turn up his engine against his team?s instructions in Abu Dhabi, indicates he was.
Hamilton usually seemed completely untroubled by Rosberg over the opening two-thirds of the season, and that was what won him the title. The late-season dip may prove a useful motivation over the winter as he prepares for another fight.
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View race-by-race notes on Lewis Hamilton
Australia ? All weekend long Hamilton seemed to have a couple of tenths of a second in hand over Rosberg in the first sector. His first run in Q3 was good enough to take pole position by almost half a second, but he lowered his time on his second run anyway. A clean start and smooth restart meant he was untroubled by Rosberg at the start of the race, and despite misleading messages from his duel read-out he kept Rosberg back in the second stint.
Malaysia ? Missed a significant chunk of Friday running due to a power unit inlet system problem. Nonetheless a rapid lap at the start of Q3 secured his second pole position of the year ? neither he nor Rosberg beat the time as the track dried. He led at the start but pitting under the Safety Car dropped him back into the back and by the time he merged Vettel was ten second up the road, and after over 40 laps of chasing the gap was pretty much the same.
China ? Fastest in every single session, except for Q1. Led all but three laps of the race en route to his second hat trick of the season. Able to control his pace and manage his tyres whilst never allowing his team mate to get within a second of his lead all race. Has now beaten his team mate to the chequered flag in all three races in 2015.
Bahrain ? Claimed his fourth pole position in a row on Sunday by a healthier margin than he enjoyed in China and Malaysia. Hamilton rarely looked threatened in the race as his team mate scrapped with the Ferraris. A last-lap brake-by-wire glitch might have proved disastrous had it struck earlier, but it didn?t stop him from winning his third race this year.
Spain ? Spun in final practice after touching the artificial grass in turn three, and from then on seemed to lose the initiative to his team mate, who beat him to pole position. A poor start cost him one place to Vettel and almost another to Bottas. Unable to pass Vettel on the track, he tried to undercut the Ferrari at the first pit stop but was thwarted by a slow left-rear tyre change. A switch to a three-stop strategy got him ahead, but by the time he?d made his extra pit stop Rosberg was too far ahead to be caught.
Monaco ? Led both practice sessions on Thursday. Didn?t seem as settled on Saturday, including in qualifying where he was kept from the top spot in Q1 and Q2. He recovered well, however, chose to be the first Mercedes in the queue following last year?s controversy, and took his first Monaco Grand Prix pole position at his ninth attempt. Led comfortably from the start and was over 19 seconds ahead of Rosberg when the Safety Car came out. Didn?t expect to lose the lead by pitting, but he did, and finished a very frustrated third.
Canada ? Despite topping both sessions on Friday he had a scruffy start to the weekend ? a spin in first practice, a bizarre crash in the second, and in the third he was last after failing to get a clean lap in before the red flags started to fly. Rosberg ran him close in qualifying but Hamilton prevailed by a comfortable margin. He pulled clear in the first stint but Rosberg kept him honest after they switched to softs, the gap rarely more than two seconds. Even so, a fourth win for Hamilton never really looked in doubt.
Austria ? Half a second off the pace on Friday and didn?t seem to be much closer to his team mate as the track dried in qualifying. Then it all seemed to click when it mattered: suddenly Hamilton found his missing chunk of time in the middle sector and claimed pole position, despite spinning at the beginning of his final lap. However his start was tardy ? Hamilton later said he wasn?t satisfied with recent changes Mercedes have made to their clutch ? and he spent much of the race chasing Rosberg. Then made life more difficult for himself by straying across the pit lane exit line and collecting a five-second time penalty, so had to accept second.
Britain ? Looked genuinely uncomfortable in the warmer conditions on Friday, but overnight changes seemed to result in a car he was much happier with. He duly took his eighth pole position of the year ? as in Austria his first lap was good enough and neither Mercedes driver improved on their second runs. Having reverted to an old clutch set-up for his start he blamed a lack of grip on his grid position for a sluggish getaway which allowed both Williams drivers past. He briefly got back in front of Bottas only to lose the position again while attacking Massa. He told the team he couldn?t pass Bottas, but his lap 19 pit stop and a flying out lap ensured he jumped both the FW37s. He had a brief off at Copse when the rain arrived, and after the track dried he began to struggle with his front tyres. However his decision to pit on lap 43 for intermediates just as the rain was returning was inspired, and won him the race.
Hungary ? Swept all three practice sessions with little drama besides the occasional lock-up, and continued his domination into qualifying where he headed all three parts and sealed his ninth pole position of the year. But his domination of the weekend ended within seconds of the start: relegated to fourth in the first few corners, he then went off at turn six, slipping to tenth (and somewhat unfairly blaming his team mate for the error). He?d fought his way back to fourth when he came under attack from Ricciardo and thumped into the Red Bull, necessitating a front wing change and earning a drive-through penalty. Nonetheless he recovered to sixth at the chequered flag and edged further ahead of Rosberg in the championship.
Belgium ? It felt like Hamilton was toying with Rosberg in qualifying ? the pair looked closely-matched in Q1 and Q2, but come the pole position shoot out Hamilton suddenly produced the best part of half a second?s advantage, most of it found in the middle sector. After a clean start ? his first in four races ? Hamilton fended off a brief challenge from Perez which constituted the greatest threat he faced all race.
Italy ? Every session at Monza ended with Hamilton?s name on top of the times sheets. Some were closer than others: Ferrari turned the wick up for qualifying and were a genuine threat, but he delivered his 11th pole position of the season and converted it into his seventh win.
Singapore ? It seemed like business as usual for Mercedes in first practice, but when the serious business began and the track rubbered in they found themselves grappling with deep set-up problems. Hamilton described the problem as a sheer lack of grip, and it appeared to affect both drivers equally ? Hamilton had his usual margin in hand over Rosberg in qualifying. A switch to soft tyres during the first Safety Car period could have set him up for an interesting run to the flag, but a power unit problem forced him out before then.
Japan ? It was nip-and-tuck between Hamilton and Rosberg on their first runs in Q3, and if Hamilton?s effort had been tidier he might have taken pole position. Soon after the start of the race that became irrelevant, however: Hamilton got down the inside of Rosberg at the first corner and exploited that advantage to its fullest. ?I had my corner and so we were very, very close but I was basically understeering, I was running out of grip,? Hamilton explained. ?I imagine Nico was running out of road, but that?s what happens when you?re on the outside.? From then on his victory looked assured, despite a mid-race lock-up which left him with a flat-spotted tyre. Once it was replaced a rapid out-lap after underline how much pace he had in hand.
Russia ? In a repeat of Japan, with minimal set-up time Hamilton wasn?t able to keep Rosberg from pole position, and he went off on his second run in Q3 as he tried to. The opening moments of the race promised an exciting scrap between the pair, but it all came to naught when Rosberg dropped out. Not threatened from behind, Hamilton only had to worry about his tyres cooling off behind the Safety Car and a minor problem with his rear wing in the closing stages.
United States ? Brushed Rosberg aside at turn one but came under pressure from his team mate and the Red Bulls before switching to slick tyres. When the track dried he moved up to second but had dropped back from Rosberg when his team mate went off, handing him the lead and cementing his third world title.
Mexico ? Rosberg had the edge on him in qualifying for the fourth race in a row, but Hamilton indicated his set-up was more race-orientated. However being snookered behind Rosberg from the start gave him little opportunity to demonstrate whether that was the case. He told his team the decision to bring him in for his final pit stop was ?wrong?, believing the tyres would last, but deciding against disobeying his team and putting his theory to the test.
Brazil ? ?I really need to improve my grid position this time because that can heavily influence the race,? said Hamilton on Friday. He didn?t ? Rosberg pipped him for the fifth race running after Hamilton?s final practice preparations were disrupted by a technical problem and a spin. He threw everything at his team mate in the second stint but was never able to force Rosberg onto the defensive, and with no strategic alternative being offered he was destined for second.
Abu Dhabi ? Made a lot of changes to the car in pursuit of a better set-up, but ended up over a third of a second off his team mate in qualifying. Dropped back quickly at the start on super-softs but was stronger on the harder tyres. But despite extending his middle strategy to shorten his final run, he couldn?t chase down his team mate.
Over to you
Very dominant in the early and mid-season, pretty much faultless. However, his form started to deteriorate as the season went on. Partly because Rosberg had upped his game, but also because Hamilton just didn?t seem able to pull it together on Saturdays.
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