On Saturday, the country's professional football players' union said that the match would not take place, but Leiria scraped together a team consisting of youth players and Benfica loanees.
Leiria fought bravely before Feirense broke the deadlock at the end of the first half. They then went on to win the match 4-0.
After the game, Leiria president Joao Bartolomeu told the press that midfielder Alphousseyni Keita, who was expected to take part in the match, stole a suitcase full of money from the club moments before kick-off.
"Keita took possession of €6,000 that was in a suitcase, stole the money and ran away with his football kit still on," Bartolomeu said.
"He had someone in a car outside [the stadium] waiting for him and we reported the incident to the police."
Leiria are currently rock-bottom in the Portuguese Liga and have avoided being punished with automatic relegation and a fine by putting a team out on Sunday.
The Portuguese Professional Football League is studying new financial protection mechanisms to avoid a repeat of the situation.
A spokesperson for the body also said that the ongoing debt crisis in the country has severely impacted the finances of Portuguese football clubs.