The 18-year-old struck with just five minutes on the clock, heading home Sergio Aguero’s cutback, to clinch a crucial three points in the Premier League title race.
The midfielder’s inclusion in the starting XI had come as a surprise to many but Guardiola asserted he has the utmost faith in the Stockport-born starlet’s ability.
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“I am a genius!” he joked. “He scored a goal. How good is the manager?!
“Yesterday, I decided he was going to play and he is more than ready. I trust him a lot. He scored a goal and felt a lot.
“I decided to play him because we wanted a specific thing – to attack more in the box. He had a few more chances because he always has the capacity to work and the ability.
“He didn’t make the best performance he can do but he played in the Premier League and it is an incredible experience.
“Phil is an incredible player. We needed this capacity to press high and he is a guy who has the quality to arrive in the box. He brings another dynamic and an extra intensity.
“Every time he plays, he has scored a goal or has chances. He has the ability to play in small spaces.
“Against Dier, Wanyama and Alli, it was not easy but he did it well.”
Guardiola also acknowledged the importance of the victory, as City took a huge step towards securing back-to-back Premier League titles.
The Catalan boss hailed the character of his players, as the team bounced back from Wednesday night’s Champions League setback.
“It was very important for the title race in the Premier League,” he added.
“We know that if we drop points, we cannot fight to the end because it’s not in our hands. If we pick up points, it’s in our hands.
“The last days were tough for us. In the sunshine, it was a tough day and a tough game.
“Ederson saved our game. It’s three more points and it’s still in our hands…
“I give more credit for this game than the previous ones we’ve had this season.
“Since I’ve been here, we have shown character. After last season, when we won 100 points, we have won two titles, we are in the FA Cup Final and we can win the Premier League.
“The team have been incredible this season. I could not have done what the players have done.
“Spurs are an incredible team and we felt incredible pressure. They had no pressure – they could not lose anything today, but we could have lost the Premier League. We also lost Kevin.
“The fans were incredible because they know it (is difficult). We gave absolutely everything. The guys and the spectators are really pleased.
“We have won the last ten Premier League games in a row. It’s not bad!
“The fight against Liverpool is the best ever. They are one of the best teams of my life. Being there, what can I say?
“We will put everything in at Old Trafford, Burnley, Leicester and Brighton and see how far we get.
“If we win, we will be so happy. If not, we will congratulate Liverpool and go again next season.”