This weekend was reserved for the fourth round matches of the 2014-15 FA Cup. At this stage, 32 teams still had hopes of winning the oldest soccer competition in the world. But the magic of this tournament is in its one-game format, where clubs from a lower tier have a chance to become giant-killers and leave a legacy. Saturday brought multiple scenarios of that kind.

The top two teams in the Premier League, Chelsea and Manchester City, had each progressed to the fourth round, and since both were drawn to play non-Premier League sides at home, they were considered heavy favorites to progress to the last 16.

Chelsea hosted League One Bradford City at Stamford Bridge, and got off to a quick 2-0 lead, but the Bantams rallied to put four past Petr Cech and stun the Premier League leaders 4-2. With the visitors in the third tier of the English system, this result certainly joins the list of the most shocking FA Cup upsets…

Defending EPL champions City didn’t fare much better at home against Middlesbrough, who are one tier below the top flight in the Championship. City created more chances in the first half, but the saying stayed true: the more an underdog keeps the favorite scoreless, the more confident they are of pulling the upset, which Boro did 2-0.

Those weren’t the only top flight clubs to struggle against non-EPL sides. Manchester United were on the back foot for much of their match at Cambridge United (the lowest-ranked team remaining in the Cup), and will host a replay at Old Trafford. Liverpool will travel to Bolton for a replay of their own after failing to beat the Wanderers at Anfield; the same goes for Sunderland, who will visit Championship side Fulham. Another Premier League team’s Cup dream is over after Swansea lost at Blackburn. One more match remains Monday, when Rochdale (League One) hosts Stoke, the runner-up in 2011.

Some may argue that the FA Cup’s popularity has gone down a little in the last few years, but more results like this in later rounds could put an end to that. It’s been a generation since a team outside the top flight won the Cup (West Ham United, 1980); are this weekend’s results a sign of that drought coming to an end?

The FA Cup Final is on May 30 at Wembley Stadium in London.