In a tense affair, Sundowns broke the deadlock through new signing Fiston Abdul Razak's 105th minute strike at Lucas Moripe Stadium.
However, Musa Bilankulu equalised with two minutes to go, with Larsen's men holding their nerve in the shootout to join holders Kaizer Chiefs, Bidvest Wits and Ajax Cape Town in the semi-finals.
Larsen singled out a few players that made an impact in their first game of the season.
"I thought few players really done well for us," he said."Alfred Ndengane in the midfield was outstanding for us. He broke down play exceptionally well and his switch of the ball in midfield was very good.
"Also there was a very positive impact from my three substitutes. I thought Ntanga, Dumsani Zuma and Lakay had a positive influence when they came on.
"But one has to give credit to my team for their fighting spirit once again. I am very proud of their performance."
The PSL will hold a draw in Johannesburg today to decide the last-four match-ups.