Mauricio Pochettino revealed his greatest joy as a coach was helping Espanyol avoid relegation, not Tottenham's incredible win over Manchester City.

Pochettino guided Spurs into the Champions League semi-finals after a remarkable second leg against City on Wednesday.

While his side were beaten 4-3, they advanced on away goals after a 4-4 aggregate draw.

However, Pochettino said keeping Espanyol, the club he played for, in LaLiga in 2008-09 during his first job as a coach was a happier moment.

"My greatest joy as a coach was in Almeria when we were saved [from relegation] because of what it meant to the whole Espanyol family," he told Spanish radio.

Fernando Llorente's 73rd-minute goal against City proved decisive, the effort standing despite a VAR review for a possible handball.

Even later drama was to come, Raheem Sterling denied a stoppage-time goal – initially given – due to an offside.

"When he scored, I looked like The Incredible Hulk," Pochettino said.

"I took off my jacket, I threw my sweater down [onto the ground] ... I sat down and then that's when they said that the VAR had disallowed it for offside.

"At that moment, I revived. The injection of energy was incredible."

Spurs will face Ajax in the semi-finals.