1) Sol Campbell, Arsenal (2001/02)

In 2001, Arsenal had hit a wall. The Double of ’98 had faded into memory and even the additions of Thierry Henry and Robert Pires had failed to revitalise a side that was slipping further away from Manchester United at the top. The nadir was reached when they conceded a third straight title to United on Easter Saturday, just weeks after crashing 6-1 at Old Trafford with a central defensive partnership of Gilles Grimandi and the less-than-irrepressible Igor Stepanovs.

Sol Campbell’s signing in mid-July reaffirmed Arsenal as a force in a way that even the arrival of a promising-but-scattergun Henry two years earlier had failed to, and overnight the team acquired a robustness that reinforced the delicate magic of its frontline. In 12 months with Campbell at the heart of the defence, Arsenal inflicted a 17-point reversal on United at the top, and claimed another double (with Sylvain Wiltord scoring this memorable winning goal at Old Trafford in 2002).

2) Luis Figo, Real Madrid (2000/01)

Three utterly bizarre things happened in Spain in summer 2000. The first is that Real Madrid finished a distant and dismal fifth in La Liga, seven points behind unlikely champions Deportivo La Coruna. The second is that they had the audacity to swipe Barcelona’s Luis Figo, their great rivals’ talisman at the height of his potency, from across the Clasico divide. The third – and 15 years later this still teases the senses – is that they succeeded.

Figo was the 15th player in over a hundred years of bitter rivalry to make the switch directly from Camp Nou to Bernebeau, but the first to shatter the world transfer record in the process. The Portuguese helped conjure a rise of phoenix-like proportions in dragging Real from upper-mid-table back to the league summit, in doing so putting a whopping 17 points between his new and former employers. £37m shrewdly invested.

3) Samuel Eto’o, Barcelona (2004/05)

Perhaps the sweetest part of 2005’s title success for Barcelona fans, quite apart from the fact that it was the first time they’d worn the La Liga crown in six seasons, was the ease with which their fresh-faced, £19m new signing Samuel Eto’o helped himself to 29 goals. The Cameroonian's sparkling debut season apparently left behind whatever hang-ups he acquired when being dismissed as surplus to requirements by Real Madrid four years earlier.

4) Robin van Persie, Man United (2012/13)

Football is often won and lost in the head. That one player’s inclusion can radically alter the way a club thinks about itself was never more apparent than when Robin van Persie defected to Old Trafford from Arsenal in 2012, just weeks after United’s supremacy had received a lethal blow from the new champions across Manchester.

Van Persie’s arrival re-asserted United as a side that could still crush even their fiercest rivals, soothing the club’s ego at a time when it was under attack from their noisy neighbours.

Remarkably, United scored fewer goals en route to reclaiming their title than they had when losing it to City in 2012, but while Roberto Mancini’s team crumpled under the pressure of leading from the top, United quietly and calmly let their new talisman fire them to a 20th league crown with 26 Premier League goals.

5) Jens Lehman, Arsenal (2003/04)

Two years after the Campbell masterstroke, Wenger repeated the trick. As David Seaman’s stellar career in the Gunners goal limped to its injury-ravaged end, the north Londoners lost out on the title in 2003 with a makeshift double act of Stuart Taylor and Rami Shaaban, the first in a long line of disastrous goalkeeping experiments.

Jens Lehman was a fine goalkeeper, but his arrival meant more than that. He added focus, steel and bite to a side so often accused of complacency in their title capitulation. His class as a player aside, Lehman’s thunderbolt impact on the mentality of a team that had begun to believe its own hype was worth a sizeable portion of Henry’s 30-goal Golden Boot-winning haul, as the Gunners went the season unbeaten.

6) Andrea Pirlo, Juventus (2011/12)

“His words assault you. They crash through the doors of your mind, often quite violently, and settle deep within you.” Andrea Pirlo is as idiosyncratic with his words as with his feet, and for former Juventus boss Antonio Conte he demonstrated both. The Italian maestro’s testimony to the man who he helped to win three Serie A titles after Juventus had suffered seven doleful years with nothing – and not least after Milan had left him on the scrapheap – is pure Pirlo. It remains to be seen if the great man will take the good times with him from Turin to New York.

7) Juan Sebastian Veron, Lazio (1999/00)

Lazio smashed their transfer record to sign Parma’s mercurial midfield engine Juan Veron in time for their centenary celebrations in 1999 – and there was an overwhelming sense that the planets were aligning. It had been 26 years since I Biancocelesti’s last and only Serie A title, but despite blowing the league title on the penultimate day of the 1998/99 season with a limp draw at Fiorentina, the club boasted stellar names and a budget to match.

The side lived and breathed by the fleet-footed genius of Sinisa Mihajlovic, Christian Vieri and Marcelo Salas, but in the close season Sven-Goran Erikson recognised that his team lacked a failsafe against the kind of late-season collapse that had scuppered their title bid, and so turned to the wrecking ball Veron. It was £18 million well spent; the industrious Argentine missed only three games as Lazio held their nerve in a nail-biting run against Juventus to barge their way to a second scudetto.

8) Eric Cantona, Man United (1992/93)

When Eric Cantona pitched up at Manchester United in December 1992, there were two obstacles to conquer. One was Mike Walker’s Norwich, sitting pretty at the top of the new Premier League table. The other was the ghost of 26 barren years at Old Trafford that even five years of Sir Alex Ferguson’s sustained attention hadn’t managed to shift.

It’s often overlooked among the myriad achievements of the Frenchman that he was largely responsible for landing the ‘difficult first title’ that had eluded them for over a quarter of a century. That his transfer from soon-to-be-deposed champions Leeds left his former club languishing somewhere near the relegation zone come May was just one more stat to confirm Cantona's influence.

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