MANCHESTER – English football's biggest teams have never experienced a day like it. Liverpool and Manchester United were both comprehensively humiliated by defeats Sunday that rank among the heaviest in their history.Just when it looked like United's 6-1 collapse at home to Tottenham would be the day's biggest shock in the Premier League, Liverpool managed to surpass it.The champions fell apart to lose 7-2 to an Aston Villa side that only avoided relegation on the final day of last season and is now one of only two sides with 100% starts.No defending champion in 67 years has lost so heavily in England.