Manchester City produced a stunning performance at the Allianz Arena on Tuesday night to beat Bayern Munich 3-2 and finish second in Group D to qualify for the Champions League knockout phases. A successful night for City was deflated only by the manager Pellegrini's admission that he had misunderstood the goal-difference rules, believing that the Blues needed five goals against Bayern to top the group, when in fact four would have been enough.
"We knew roughly," he said. "We didn't know if 4-2 would be enough or if we would need 5-2. We thought it needed to be 5-2, to be honest."
Pellegrini is not the only manager to have not fully understand the rules of the game. Here are five other examples of coaches dropping the ball …
When goal difference makes no difference
In 2011, Pitso Mosimane's South African team failed in farcical fashion to qualify for the Africa Cup of Nations after misinterpreting the rules of their group. Bafana Bafana were under the impression goal difference would be the deciding factor for qualification, when in fact it was the teams' head-to-head records that would prove all important. Comfortably ahead of Sierra Leone and Niger on goal difference, South Africa decided to play for a draw. It was only after celebrating on the pitch that the news reached the jubilant players and coach that they had actually not qualified, Niger had.
"I feel like I have failed", said Mosimane, before describing Africa as "a jungle" and writing to the Confederation of African Football to try to get the rules changed.
Never trust hearsay
The 1995-1996 Premier League relegation battle was a nail-biter, with Manchester City, Southampton and Coventry City all level on 33 points, and Queens Park Rangers and Bolton certain for the drop. Alan Ball's Manchester City were occupying the final relegation place, and with a goal difference seven below the other sides. Drawing 2-2 with Liverpool on the final day of the season, City were depending on either Coventry or Southampton to lose to avoid relegation. So when the news came through that Southampton were indeed losing – 1-0 to Wimbledon – Steve Lomas was ordered to play for the draw, dragging the ball to the corner flag to waste time.
The information, however, was wrong. Southampton were not losing, and City needed a win after all. "I had gone off 15 minutes from time and was watching it on TV," said Niall Quinn. "So I had to run up the tunnel and get the message on that we needed another." They didn't get it, and City were relegated.
Last month the Milan director Umberto Gandini took responsibility for M'Baye Niang not being able to play in the Champions League after the Rossoneri became confused over players' eligibility for A lists and B lists. Niang missed out on his place on the A list to Stephan El Shaarawy, with Gandini apparently unaware that El Shaarawy, being born after January 1992, was eligible to play for the B list, thereby freeing up a spot for Niang on the A list. As it is, Niang can now not play at all, after the deadline was missed to change selection choices.
Milan issued the following statement: "Umberto Gandini regrets this error and apologises to all parties concerned, as well as professionally to the Rossoneri fans."
In light of Pellegrini's embarrassing oversight at the Allianz Arena on Tuesday night, the Scotland manager Gordon Strachan decided to come clean about his own indiscretion when it came to understanding the rules of qualification.
Strachan admitted he got it wrong in 2006 when a 1-0 victory against Manchester United in the Champions League group phase ensured his side's progression. The Scot had mistakenly thought his side were out of the competition until he was informed post match, apparently by ITV's Gabriel Clarke.
"Gotta say, I've been there," he said, speaking as an ITV pundit. "Got through with Celtic once, didn't realise we'd qualified. I think it was Gabriel who came up to me after the game and said: 'Well done, well qualified'... pardon?"
"Manchester United had beaten us 3-2 and we'd beaten them 1-0 and we went through on away goals."
Always read the small print
Three years ago Internazionale were left kicking themselves after they found out the new signing Diego Forlán, who they had hoped to include in their 25-man Champions League squad, was ineligible to play in the competition as he had already appeared for Atlético Madrid in the Europa League. The club realised when they tried to register the striker before the group phase started.
"The truth is that I did not know the rules from Uefa," Forlán said at the time. "I based myself on what I had been told, that is that I would be eligible as long as I did not play against Vitória Guimaraes. I had spoken to Atlético about not playing against Guimaraes as I knew I would be moving to Inter."
Forlán was cleared to play in the knock-out phase, however, and featured against Marseille in the last-16 ties, where his side went out.