Fernando Llorente was the hero but Spurs are indebted to Son Heung-min’s courage and selflessness

That Llorente scored the winner to dispatch Watford 2-1 was nowhere near as impressive as Son getting through a full 90 minutes on his return from Asian Cup duty

No Harry Kane, no Dele Alli, no problem for Tottenham, although it took them a while to get there. Fernando Llorente and Son Heung-min both started and both scored for Spurs last night, the former rather more surprising than the latter.

And yet for all the love and gratitude showed to Llorente, the real hero of the night was Son. He was the man who only arrived back in London from the UAE on Saturday, drained from his efforts in the Asian Cup. But he worked himself hard in training just to get ready again for Watford on Wednesday.

Pochettino revealed that Son was “disappointed” that South Korea lost their quarter-final to Qatar, but admitted that he was himself “happy” to have Son back at such a crucial point in the season. And on this evidence it was very clear why.

It was never in Pochettino and Jesus Perez’s plan for Son to play all 90 minutes last night but that was what ended up happening. At 1-0 down with 10 minutes left they could never afford to lose their best finisher. “It was not in the plan for Son to play 90 minutes,” Pochettino revealed in his post-match press conference. “But with the result, we spoke to Jesus and said maybe we need to take a bit of a risk, to keep him playing.”

So Son stayed on, a decision he thumpingly vindicated when he picked up a loose ball in the box and smacked it beyond Ben Foster to make it 1-1. Llorente won Spurs the game, but without Son they would have lost it. And Pochettino was thrilled, not just with the goal, but with the example. Son’s courage and selflessness were held up afterwards as just what Pochettino wants from his players.

“It was an amazing effort from Son tonight,” Pochettino said. “From the beginning he showed energy. I am so happy with his performance, but more happy because he showed massive commitment to the team. That is so important to tell everyone. The energy he spent, the commitment he showed, is very good from him. He is always available to deliver the job you expect from him.”

By the end Son looked exhausted, having left everything on the pitch far sooner than anyone expected. Pochettino did not sound confident when discussing whether Son might play another 90 minutes here against Newcastle United on Saturday. If he does not recover well from all this then he might have to be on the bench at the weekend.

Son Heung-min sacrificed himself to play a full 90 minutes for Tottenham in the win over Watford (Reuters)

But there are more important challenges ahead, not least Borussia Dortmund here in two weeks’ time. Out of both domestic cups, those two games now rise above everything else as the two that will define this Tottenham season. Beat Dortmund, and reach their first quarter-finals since 2011 and this season will be a clear success. And yet they will have to do it without Harry Kane and Dele Alli, both men injured at precisely the wrong time.

Dortmund will not rest easy knowing that Spurs still have Son. His speed, intelligence and ice-cold finishing make him a threat to any defence, especially one that plays as aggressive a game as Dortmund. They should remember last season in the group stage, when Son shredded their defence, scoring the opener when Spurs won 3-1 at Wembley, and the winner when they won 2-1 in Germany. With no Kane and no Alli, at least for the first leg, the returning Son will be more important than ever.