Having collected one point from their first three games, Tottenham's UEFA Champions League campaign looked over before it had properly got going. UEFA.com breaks down the London club's rollercoaster ride ahead of their semi-final against Ajax.

SPURS V AJAX BUILD-UP

Why the slow start?

Nine Spurs players featured in the semi-finals of the 2018 FIFA World Cup – more than any other club – but Tottenham's stuttering start to their UEFA Champions League campaign was the result of a demanding schedule and on-field defensive uncertainty.

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The north London club were slack at the back, conceding eight goals in their first three fixtures against Internazionale, Barcelona and PSV Eindhoven, with Hugo Lloris far from his best in the latter two fixtures. With just one point to their name halfway through the group stage, Tottenham's hopes were "nearly over" and there was "minimum possibility" of reaching the next stage according to Mauricio Pochettino.

When was the turning point?

Last-gasp wins against PSV and Internazionale on matchdays four and five kept Tottenham's destiny in their own hands – the former of which Harry Kane described as meaning "everything" – but perhaps the moment that gave Spurs belief they could go this far came at the Camp Nou, where Lucas Moura struck late to salvage a 1-1 draw with Barcelona, which, combined with Inter's draw with PSV, sealed Tottenham's place in the last 16.

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"After the 2-2 draw in Eindhoven, no one believed in us. All said mission impossible. But we are here," said Pochettino after his side became just the eighth in history to reach the knockout stages having had just one point from three games. "I always said anything is possible in football if you have faith and quality. I never said it was impossible."

What's changed?

As the season has progressed, Tottenham's defence has returned to its miserly ways of seasons past. The Lilywhites too often relinquished the early initiative in the group stage, allowing five goals inside the opening half-hour in their six games, but Toby Alderweireld and Jan Vertonghen have since excelled and Lloris' single-handed efforts to repel Borussia Dortmund and Manchester City embody his – and the club's – improvements since the turn of the year.

Heung-Min Son has been key in Tottenham's run to the last four ©AFP/Getty Images

Spurs have also developed a habit of scoring late in continental fixtures, with eight of their last 12 goals coming in the last 15 minutes. Having contributed a third of those 12 goals, Heung-Min Son's form has been pivotal, as has that of Moussa Sissoko in midfield, while the return of Christian Eriksen and Dele Alli to their best has brought an unpredictable, mischievous streak to Tottenham's attacking play.

Who has been the key man?

Pochettino called his players "heroes" after reaching the last four, and while it has been a collective effort, there have been individuals worthy of particular praise.

French pair Moussa Sissoko and Hugo Lloris have been influential ©Getty Images

Son has been magnificent, scoring in three of four knockout fixtures so far and stepping up whenever Kane has been unavailable, while Sissoko has been a revelation in midfield following the departure of Mousa Dembélé. Fernando Llorente, meanwhile, has been a potent weapon from the bench, returning two goals and an assist in just 95 minutes of European action this season.

Most of the credit, however, must go to Pochettino, who has masterfully guided Spurs through a period in which they have made no signings, moved stadiums and suffered several injury crises, in the process turning the north London club into one of Europe's most formidable, attractive sides.

Where will the semi-final v Ajax be decided?

On the field, this tie could well be decided in midfield, currently an area of concern for Spurs with Sissoko and the influential Harry Winks both doubtful for the first leg. Victor Wanyama stepped up manfully against City and Eric Dier is fit again, but coping with the energy, craft and dynamism of Frenkie de Jong, Lasse Schöne and Donny van de Beek is a tough ask.

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There is likely to be some pre-tie talk about the 'Spursy' tendency, the club's supposed propensity to snatch defeat from the jaws of victory at key moments. Spurs might have lost domestic semi-finals to Chelsea (twice) and Manchester United in recent seasons, but choosing to focus on that would be wilfully ignoring the evidence of this UEFA Champions League campaign, during which Pochettino's charges have demonstrated their increasing maturity with every passing round. This is as good an opportunity as any to dispel that myth permanently.

How big an achievement is this?

The timeframe alone underlines the scale of the achievement: it bears repeating that this is Tottenham's first European Cup semi-final for 57 years, and their first in the UEFA Champions League era. That such an occasion comes within weeks of the move to a sparkling new stadium only adds to the sense that this is an upwardly mobile club with a bright future.

Yet this is the sort of level towards which Pochettino and Spurs have been building: those domestic semi-final exits and Premier League near-misses have served to fuel the sensation that a major trophy has eluded a golden generation in north London. This is, therefore, no time to stop and admire the view.