Malaga's long-suffering fans have endured a roller-coaster ride since Sheikh Abdullah Al Thani, a member of the Qatar royal family, bought the Costa del Sol club in 2010 after they narrowly avoided relegation.
Hefty investment in players and the hiring of former Real Madrid and Villarreal coach Pellegrini yielded a top-four finish last term and a place in Europe's elite club competition.
Al Thani's lieutenant eventually announced Malaga were undergoing an "internal restructuring" to bring them into line with UEFA's Financial Fair Play rules.
Their dream run appeared to be coming to an end after 2004 winners Porto beat them 1-0 in last month's last 16 first leg in Portugal.
"The atmosphere in the stadium was incredible and the fans deserved a victory like this," Pellegrini said in an interview with Spanish television broadcaster Canal Plus.
"It has been an unusual year," added the Chilean when questioned about Malaga's financial difficulties.
"The team deserves a lot of credit for what they have done both in the domestic league and the Champions League.
"They maintained their focus on the sporting side and had the capacity to get to grips with all the other problems.
"Then there was a positive atmosphere coming from a desire to help the club and the players deserve huge praise for that."
Malaga's success has been built around a squad mixing experienced campaigners like Argentine centre-back Martin Demichelis, French midfielder Jeremy Toulalan and Paraguay forward Roque Santa Cruz and youngsters like Isco.
The talented 20-year-old, who is on the fringes of the Spanish national team, was voted by coaches the 'revelation player' of La Liga last season and he won the 'Golden Boy' trophy as the best under-21 player in Europe.
But it is Malaga's old timers who have really underpinned their s
