IT wasn’t the most expensive footballer in the world — £89million Paul Pogba — who made the difference.
Nor one of the most famous players on the planet, Zlatan Ibrahimovic, as he arrived at the richest club on Earth alongside perhaps its greatest current manager, Jose Mourinho.
Nor was it £47.5m John Stones, nor £37m Leroy Sane as they joined the Pep Guardiola revolution at Manchester City.
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No, it was Marcos Alonso — once relegated from the Premier League with Bolton — and Victor Moses, who’d spent the previous two seasons in and out of starting line-ups while on loan at West Ham and Stoke.
These were the unlikely heroes who transformed the 2016-17 season in favour of Chelsea.
On October 1, Antonio Conte took his weather-beaten Chelsea side to Hull, with mutterings about the Italian’s own Stamford Bridge future already being heard, following back-to-back defeats against Liverpool and Arsenal.
Yet Conte had the courage of his tactical convictions as he switched to the 3-4-3 system he’d often favoured at Juventus, employing summer signing Alonso and perennial fringe player Moses as dynamic wing-backs who made the whole thing tick.
Chelsea’s 2-0 win at the KC Stadium barely registered that week.
Europe were losing the Ryder Cup, Sam Allardyce was losing the England job, Guardiola’s City were losing their 100 per cent league record at Tottenham and Mourinho’s United were setting the sluggish tempo for their league campaign with a 1-1 home draw against Stoke.
What happened next for Chelsea was extraordinary, though — a Premier League record of 13 consecutive victories, including ten clean sheets, stretching to the new year.
Most significantly, this streak included landmark victories over both Manchester clubs, whose Hollywood managers had been expected to duel for the title.
United were hammered 4-0 at the Bridge, as Chelsea seized the initiative after 30 seconds with a goal from Pedro, who Mourinho had hijacked from United for the Blues 12 months earlier.
Mourinho was taunted with chants of ‘You’re not special any more’ at the club where he had won three titles but left in disarray.
This was a ghostbusting victory, fumigating the stench left by the fallout between Mourinho and players then branded ‘rats’ by their own supporters.
Soon after, at the Etihad, Chelsea roared back from one down to win one of the games of the season 3-1 — City left rueing a glaring close-range Kevin De Bruyne miss at 1-0 before Sergio Aguero and Fernandinho were sent off in an injury- time meltdown.
Guardiola’s team won their first ten matches — yet ended up as the only one of England’s ‘big six’ to finish the season with nothing to celebrate.
The force was with Conte and Chelsea rarely looked back.
Two identical Dele Alli goals in a 2-0 defeat at Tottenham ended the winning streak, one short of the all-time English record, and it was Mauricio Pochettino’s vibrant young Spurs who would provide Chelsea with their only competition down the straight.
United and City were nowhere near, Liverpool’s challenge fell apart during a winless January and Arsenal were consumed by familiar civil war over Arsene Wenger’s future — right up until they denied Chelsea the Double with Saturday’s shock FA Cup final triumph.
The Blues recovered instantly from that Spurs setback with a 3-0 thumping of fallen champions Leicester, with two goals from Alonso, as N’Golo Kante returned to his former home in the form which would see him earn the Footballer of the Year and PFA Player of the Year awards, as well as a second successive title with different clubs.
Chelsea’s other significant summer signing, the returning David Luiz, provided one of the season’s most instinctively brilliant moments with a stunning free-kick to catch out Liverpool keeper Simon Mignolet during a 1-1 draw at Anfield.
Conte’s side rumbled on relentlessly — save for a late wobble which brought defeats by Crystal Palace and Manchester United — before hopes of a dramatic title-race climax were snuffed out when West Ham defeated Tottenham.
Spurs departed White Hart Lane with 17 consecutive victories at their spiritual home before Harry Kane secured a second straight Golden Boot and closed in on Pele’s career record of 1,283 goals . . .
But even Spurs, in their best league campaign since 1963, could not match the title-winning pedigree of Conte and Co.
It was the season when Chelsea waved goodbye to captain John Terry, and United, more than likely, to theirs too, with Wayne Rooney’s career in steep decline.
The campaign also brought us spectacular scorpion kicks from Henrikh Mkhitaryan and Olivier Giroud, trumped by Andy Carroll with his strike against Crystal Palace.
There was Leicester’s capitulation from title-winning troops to relegation-haunted chumps, which earned Claudio Ranieri one of the English game’s most controversial sackings, just nine months after he had overseen its greatest miracle.
Then a revival under Craig Shakespeare, a surge to Premier League safety, a Champions League win over Sevilla and a near-miss against the crack unit of Atletico Madrid.
The Foxes were England’s last men standing in the Champions League after Tottenham’s Wembley hoodoo saw them exit early, before Arsenal were annihilated 10-2 by Bayern Munich and City were outgunned by Monaco’s young tyros in an orgy of goals.
Paul Clement quit as assistant at Bayern Munich to take over at Swansea and engineer a relegation jailbreak.
Allardyce’s rescue act at Palace included victories over Chelsea, Arsenal and Liverpool, which allowed for a few final toots on his own trumpet before Big Sam announced his retirement.
Pending offers from the Chinese Superleague, perhaps . . .
Sunderland, under ‘energy vampire’ David Moyes, slipped out of the Premier League in insipid fashion and there were relegations for Middlesbrough and Hull.
While Mourinho’s United finished sixth, they were redeemed by successes in the League Cup and the Europa League.
The FA Cup was illuminated by Lincoln City, who won at Burnley to become the first non-league side since 1914 to reach the quarter-finals, as well as Sutton United — whose glory runs were both eventually ended by Arsenal, who then became pedigree underdogs themselves in the final.
Led by the impressive Cowley brothers, the Imps then returned to the Football League — replacing Leyton Orient, who were victims of footballing arsonists in their boardroom.
Brighton once suffered a similar fate, losing their ground and almost their Football League status, 20 years ago.
Next season, the Seagulls will return to the top flight, proving that football always offers hope, however distant.