Shanghai beat Guangzhou, twice winners in the past, on penalties and in Villas-Boas' post-match press conference, he hinted at a conspiracy against his team, in events leading up to the match and also in the Iranian referee's decisions.
The former Tottenham Hotspur and Chelsea manager made the extraordinary claims during an explosive rant against Guangzhou following the dramatic quarter-final second-leg tie.
"This is the greatest achievement for SIPG ever because it's against a club that is dominating the AFC".
After a tense and action-packed second leg, which nine-man SIPG won on penalties after Guangzhou had overturned a 4-0 first leg deficit to take the game into extra-time, Villas-Boas rolled off a lengthy list of grievances.
Despite seeing his side advance to the last four for the first time in the club's history, Villas-Boas focused on the perceived injustice across the two legs.
Guangzhou's Ricardo Goulart, who scored a hat-trick over the preceding 120 minutes, missed the opening spot kick to leave Yu Hai to score the victor for SIPG at the end of a remarkable quarterfinal that ended 5-5 on aggregate.
"Yan Junling is suspended for the first leg of the semi-final because the referee gave him a yellow card". But with minutes left in the game, Wang Shenchao of Shanghai SIPG fouled Muriqui inside the area and saw a red card while Goulart completed his hat-trick from the spot to take the game to the shootout. "We come here on the bus for this game and the same two cars separately had three accidents in front of us", Villas-Boas told China's online That's magazine.
However, Hulk's 110th-minute strike helped the game go to penalties with an aggregate score of 5-5, after Guangzhou's Ricardo Goulart levelled things in the 118th minute. "This is the problem", he said.
"This club can do everything, they can cause accidents in front of us, they have players who can elbow [Brazilian midfielder] Elkeson and not be suspended and yet we won".
Elsewhere, Guangzhou coach Luiz Felipe Scolari also questioned the referee, while praising his side for their comeback.
"This is the biggest victory for SIPG and for these players, who gave everything until the end". On the contrary, I congratulate them.
"I am so determined to win the Asian Champions League title with Al Hilal because it is the only tournament I have not been able to achieve with my team", said 27-year-old Brazilian Eduardo.