Triumphant Hearts boss Paulo Sergio was overcome with joy and emotion after his side's incredible extra-time victory at McDiarmid Park to reach the William Hill Scottish Cup quarter-finals.

A Murray Davidson howitzer with seven minutes remaining looked like it would end Hearts' interest in the tournament for another year before Suso Santana won a penalty - bravely converted by Jamie Hamill with the last kick of the ball to force extra-time and end the Jambos' penalty jinx.

The game looked set to head for kicks from the penalty mark before a late flurry from Hearts forced a corner and - after David Templeton's effort smashed off the bar - the ball dropped to captain Marius Zaliukas who rammed the ball home to win the game for the Jambos with just three minutes remaining.

While many had consigned the Jambos to defeat, Paulo remained optimistic and knew his team would fight until the final whistle of referee Brian Winter.

He said: "I put Marius to centre-forward because I believed we could still get something from the game. We played a different style to our normal style as part of our strategy. I put Obua up front with Elliott so I wanted to change things. It was not a beautiful game but St Johnstone never created chances tonight and our plan worked. My team has played four games in nine days and they are very tired.

"We won this game with a lot of blood and sweat left on the field, although I must compliment St Johnstone's staff and players but it's a cup game, and it could have been them sitting here talking about what I am talking about. I am so happy but they made it very hard for us."

While St Johnstone were understandably unhappy with the award of the penalty kick, Paulo remained neutral in his thoughts on the award: "If you have images to show me I can give you my thoughts. There were so many players in the box so I couldn't see. I haven't spoken to Suso yet so I have no opinion at this moment."

Marius Zaliukas is likely to nab the headlines in tomorrow's papers after his sensational winner and Paulo was thrilled with his captain's contribution, claiming that it was the skipper's attacking ability that led to him being placed up top as an auxiliary centre-forward.

Paulo said: "I put Marius up front to score! I don't want to single out any individuals however. I made all my substitutions so we could win the game, we didn't want to wait for extra time and then for penalties. With Marius up front we had a different thread. Obua couldn't handle any more time, he was very tired but I am delighted to be through."

Despite a long run in the cup being healthy for the club's finances, the Portuguese gaffer was simply focused on having success in the cup for sporting reasons, honour and pride: "When you are in the cup, you want your team to win. Even if you coach a lower league team, you know if you win one game you can go as far as you want. If you respect your opponents, you can always progress. We know we have St Mirren now. The last game, the 5-2, means nothing now. They are a good team with a good coaching system, very nice people, so it'll be hard. But it's what we want, we want to be there and we want to go all the way."

Today on HeartsTV - post-match reaction from Paulo Sergio and Marius Zaliukas.