They then used the passes to take others into the stadium for a fee to watch the performance. Hardgrave helped two teenage girls into the stadium by donning one of the passes and handing each of the girls a forged pass to wear.
Once inside the girls paid Hardgrave SG$200 ($213) which he handed over to Penk.
The Kiwi did the same for five other people, who paid him a total of $450. Together, the men collected $1050 from their fraudulent use of the forged passes.
Tickets for the concert, held on November 11 and 12, cost between $108 and $248.
They were then detained by stadium staff, the Straits Times reported.
British man Martin Keane was jailed for similar offending. He took four people into the concert on two occasions and collected $250 from each of them.
He split the proceeds with an Australian, Paul Cosgrove, who had planned to do the same thing.
Cosgrove had been charged with scheming with another Briton, Luke Simon McKay, and Keane to use forged passes.
He was offered a bail charge of $10,000 and his case would be mentioned next Tuesday. McKay had also been charged and would be back in court on December 8.