Carlos Carvalhal believes his words of wisdom – delivered in English – are finally helping to tap the potential of his fellow Portuguese star Renato Sanches.

Swansea City manager Carvalhal witnessed another improved performance from Sanches, despite the club suffering another damaging defeat at home to Tottenham on Tuesday night as they lost 2-0 – a result which leaves them at the bottom of the Premier League and four points from safety.

But Sanches was at the heart of most of the Swans’ better periods and his energy and drive from midfield in the second-half almost sparked a recovery before Dele Alli’s late goal – doubling the Spurs lead given by former Swans striker Fernando Llorente – killed off those hopes.

Afterwards, Carvalhal was asked what he had done to re-invigorate Sanches’ loan spell from Bayern Munich as the 20-year-old had cut a mostly demoralised and uncertain figure when given his opportunities under former manager Paul Clement.

“Renato is only 20. He’s a boy,” said Carvalhal of his young countryman, who was considered one of the brightest prospects in the European game when he helped Portugal win the European Championships 18 months ago in France.

“He does not know everything about football, but he’s in a process. He must learn and get confidence.

“We gave him a clear role in the Watford game and also in this game. I believe he will play at a better level in the future. Swansea have a very good player, but he’s a boy who is still learning.”

When it was suggested to Carvalhal that his ability to communicate to Sanches in their native tongue may have helped improve the message given, Carvalhal added: “I talk with him in English most of the time, like all the other players.

“He needs a role and confidence and he will have a big part to play in the second half of the season. I am certain of that.”

Carvalhal refused to blame the officials for his side’s defeat after the game, despite two controversial decisions which went in Spurs’ favour.

Llorente’s goal was clearly offside and Spurs defender Davinson Sanchez could also have been sent off for two bookable offences.

The Colombia centre-back escaped a red card from referee Bobby Madley and was quickly substituted by Tottenham boss Mauricio Pochettino.

Carvalhal said: “I will not start talking about the referees. The linesman on the right side apologised, it’s part of the game. I do mistakes also.

“The coach of Tottenham did a clever substitution to put the centre-half (Sanchez) off because everybody knows why.”

The defeat means Swansea remain bottom of the Premier League, with Carvalhal unable to build on their win at Watford when hosting Spurs in his first home game in charge.

Carvalhal said that while he would like to add to his side in January, he is happy with the quality he has seen since taking over.

“What I have seen in these two games, I know I have a team with quality and character. They were brave and fought a lot,” Carvalhal added.

“They were disciplined. Let’s see if we can achieve one or another player in the market, but if not, I will be with these players, and if they play like this, with the commitment and soul, I am a happy coach, and we can achieve points.”

When asked whether he has money to spend in this month’s transfer window, Carvalhal smiled and gave a cryptic answer which suggested finances offered to him would be tightly controlled.

He added: “I don’t know. We don’t have petrol in the city, do we? But we have a lot of work to do, so  maybe after this game we can find some petrol.

“I am very happy with the team and the commitment as we don’t have too many players.

“At this moment, we don’t have a right back to play. Angel (Rangel) is injured and Kyle (Naughton) is suspended for three games.”