Ajax beat Tottenham 1-0 in the Champions League semi-final first leg on Tuesday.

Here AFP Sport looks at three things we learned from the clash at the Tottenham Hotspur Stadium:

Pochettino comes back down to earth

Speaking ahead of the first leg, Tottenham boss Mauricio Pochettino challenged his players to “set your dreams to infinity and beyond” as he looked to lead the club to their first European Cup final.

But Pochettino’s amusing decision to reference the catchphrase of Toy Story character Buzz Lightyear wasn’t the most significant of his pre-match comments.

Complaining about Tottenham having to play West Ham on Saturday while Ajax benefitted from having their domestic match postponed, Pochettino admitted his players looked “stressed and fatigued” during the 1-0 defeat against West Ham.

It was the same again against Ajax as the Dutch youngsters looked far more energetic and composed, while Tottenham were largely a damp squib in their first European Cup semi-final for 57 years.

After watching Ajax give his side the runaround in the first 25 minutes, Pochettino came to the touchline with a bewildered expression, telling his players to switch from a 3-5-2 formation to a 4-4-2 system in a bid to restore order.

But Tottenham’s plight was summed up by the sight of Jan Vertonghen covered in blood and on the verge of throwing up on the side of the pitch after the defender was forced off with what looked like a concussion following an accidental clash with team-mate Toby Alderweireld.

The introduction of Moussa Sissoko as Vertonghen’s replacement gave Tottenham more bite, but it wasn’t enough to stop the north Londoners crashing back down to earth.

Spurs lack cutting edge

With top goalscorer Harry Kane injured and South Korea forward Son Heung-min suspended, Tottenham were painfully short of quality up front.

Kane and Son were watching from the stands as Brazilian Lucas Moura started alongside Fernando Llorente in Tottenham’s attack.

But neither understudy was able to do a convincing imitation of their absent team-mates and Tottenham were fatally undermined as a result.

It didn’t help their cause that Christian Eriksen and Dele Alli, Tottenham’s two playmakers, were well below their best as well.

Trailing in the first half, Llorente, unmarked and just eight yards out, had a golden chance to equalise when he headed woefully wide.

Llorente was targeted with a flood of long balls and crosses as Pochettino tried to bludgeon Ajax into submission, but the Spaniard got little change out of Ajax’s well-marshalled defence.

Lucas was even more anonymous and Tottenham will welcome Son back with open arms for the second leg.

Ajax young guns show their class

Ajax are four-time European champions with a rich history of producing some of the continent’s finest players and, on the evidence of this mature display, their latest crop of wonderkids are worthy successors to Johan Cruyff, Marco van Basten, Patrick Kluivert and Dennis Bergkamp.

The average age of Ajax’s starting eleven in the Champions League this season has been 24 years and 257 days, with their line-up against Tottenham the youngest of any Champions League semi-finalist for the last six years.

But any thoughts that the Dutch club might be gripped by stage-fright in their first Champions League semi-final since 1997 were quickly erased.

Surprise wins over Real Madrid and Cristiano Ronaldo’s Juventus in the knockout stages had announced Ajax’s as Europe’s most coveted rising stars.

Once again they rose to the challenge, capping a superb start by taking the lead in the 15th minute when Donny van de Beek’s cool finish survived a VAR review.

With Frenkie de Jong, who has already agreed to join Barcelona next season, dominant in midfield and Ajax’s 19-year-old captain Matthijs de Ligt, who wasn’t born when they last reached the semi-finals, imperious in defence, the visitors were able to weather a Tottenham revival in the second half.

A Champions League journey that started for Ajax in the qualifying rounds in July and August could be about to culminate in a final appearance in Madrid 11 months later.