Pallardo is one of 42 people accused of fixing the result of a La Liga match between Levante and Real Zaragoza at the end of the 2010/11 season. He strongly denies any wrongdoing and has appeared in court at Valencia's City of Justice to give evidence.
Prosecutors claim €965,000 was paid to Levante's players to lose the match on the final weekend of the season. Zaragoza won 2-1 to safeguard their place in Spain's top flight, with Deportivo La Coruna relegated as a result.
Pallardo played the full 90 minutes in the game but insisted he had no motivation to lose. He was on loan at Levante from Getafe at the time, and a Levante win would have guaranteed his parent club were safe from relegation.
He then joined Levante permanently that summer and would later move to Hearts in 2014, where he made 43 appearances and won the Scottish Championship title in 2015.
Anyone found guilty of match-fixing could potentially face two years in prison and a six-year football ban, although all of the accused have denied any involvement.
Pallardo, now 33, said: "I had to win that game because I belonged to Getafe, which was saved if we won. Winning the game assured me to be in first [league] the following year."
A report from Spanish tax authorities on Pallardo's banking activities at the time was presented in court. There were no payments made to him between May 14 and September 14, 2011 except two amounts of €300. However, 141 days prior to the Levante-Zaragoza match, the player withdrew €18,000.
"In June 2011 I get married and many guests give me the wedding presents in cash," explained Pallardo. "In July we started pre-season and spent almost nothing. My wife goes to her parents' house in town and in August I am pulling [money from] a card," he explained.
He did open a bank account in which he received €11,300 as wedding gifts. Pallardo denied any wrongdoing: “There was never anything. It was a very close game. If it lasts ten more minutes, we could have tied or won," he said.
Another former Levante player, goalkeeper Manolo Reina, agreed with his former team-mates that he did not receive "any offer from Zaragoza" or any of the members of the Levante squad. "I did not participate in any meeting that talked about compensation for letting us lose," he said.
Other players accused include Ander Herrera, now with Paris Saint-Germain, former Leicester midfielder Vicente Iborra, former Atletico Madrid captain Gabi Fernandez, River Plate midfielder Leonardo Ponzio, Serbian defender Ivan Obradovic, Lazio forward Felipe Caicedo, Itailan defender Maurizio Lanzaro and Uruguay striker Cristhian Stuani.
Spanish league president Javier Tebas also testified, claiming a former Zaragoza player told him the result was fixed. Tebas did not reveal which player made the allegation but said the person in question did not want linked to the investigation out of fear of retaliation from other players.
A lower-ranked Spanish court had initially shelved the case but it was reopened last year after an appeal by prosecutors in Valencia, where the match was played.
Witnesses are cited to appear when the case continues next Thursday, September 19.