The Algerian broke the deadlock with the spot kick just a few minutes before half-time before going on to claim City’s first ever hat-trick at Wembley in the second period.
The 3-0 win earned us a place in June’s FA Cup final at the same stadium.
With Erling Haaland also on the pitch at the time, there was discussion over which player would step up.
However, Guardiola has stated he allows the players to work it out between them and praised his winger for taking the challenge on.
Riyad Mahrez reacts to FA Cup semi-final win over Sheffield United
“I don’t say who is the taker,” he said.
“When both [Mahrez and Haaland] play they talk to each other and it’s fine. As long as they score I don’t care.
“Erling missed the first one in Munich but his courage is great. And what like most about Riyad is that he has missed penalties in the past and he’s said ‘give me the ball again.’ That defines the player.
“I remember Erling after the game in Munich I asked him what he though when he missed the penalty and he said I’m going to score next.
“Not the next penalty, the next action. That defines the top players, they don’t live in the past.”
Check out the manager’s thoughts on our performance at Wembley in full above...
