Wigan have wasted little time in issuing a statement to condemn the actions of the supporters who ran onto the pitch at full-time, and stressed that the violent scenes were "inappropriate" and confirmed that a full investigation will be carried out. "They're favourites for the Premier League, the Champions League - and a League One club has just knocked them out of the FA Cup".
Northern Ireland striker Will Grigg, centre, fires Wigan into the lead against Manchester City at the DW Stadium.
They were overwhelming favourites against opponents fighting for promotion from League One. "I'm sure Southampton are as shocked as we are because they were probably thinking how disappointed they are going to the Etihad".
It was otherwise a very strong City side that Wigan overcame, but Guardiola had no complaints over his team's efforts.
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It struck at 5:39 pm (2339 GMT) at a relatively deep 24.7 kilometers, said the USGS . "To be honest, we're all pretty upset". Ecuador's President Lenin Moreno said via Twitter " Mexico has suffered a new natural disaster of 7.5 degrees".
It was the first time the Latics had faced the Premier League leaders in almost four years, when the sides incidentally met in the FA Cup final - Wigan won that encounter before getting relegated.
However, in spite of his obvious anger at the time, Guardiola steered clear of criticism of the official after the final whistle. I judge my players on intentions, not results, and the intentions were good.
Guardiola also said: "I was in the locker room, I didn't see it".
Chief Superintendent Stuart Ellison of GMP's Territorial Commander for Wigan, said: "Football is a family event and the disruption that players and fans alike faced last night will not be tolerated".
While it appeared that only a yellow would be issued, the referee changed it to a red and City was down to 10. It's safer when the fans are not there but sometimes it happens.