Lincoln City pulled off one of the great FA Cup upsets as Sean Raggett's late goal secured the fifth-tier outfit a 1-0 victory at Premier League club Burnley and a place in the quarterfinals for the first time in their history.
Raggett scored the dramatic winner with an 89th-Minute header that Clarets goalkeeper Tom Heaton could only push away once it had crossed the line, sending the travelling Imps fans into delirium.
Championship side Huddersfield Town earned themselves a fifth-round replay with Manchester City after holding Pep Guardiola's men to a 0-0 draw at the John Smith's Stadium.
Huddersfield thought they had taken the lead in the 27th minute after Philip Billing forced the ball over the line following a corner, but the goal was disallowed for offside.
City went close to breaking the deadlock shortly before the break through Sergio Aguero but was thwarted by Joel Coleman, with Huddersfield able to keep out the Premier League side in the second half.
Pedro Rodriguez and Diego Costa were on target as Chelsea booked their place in the next round with a 2-0 victory against Wolves at Molineux.
Wolves nearly opened the scoring just five minutes in when former Chelsea player George Saville fired a strike against the post with Asmir Begovic seemingly beaten, before Andreas Weimann sent the rebound over the bar.
Chelsea fashioned a good opportunity just after the hour-mark when Diego Costa managed to shake off his marker inside the area, but he could only send his effort into the side netting.
But the visitors did manage to find the breakthrough after 65 minutes when Willian picked out the unmarked Pedro at the far post, who headed home past Carl Ikeme into the bottom corner, before Costa sealed the win with a close-range finish in the closing stages.
Ten-man Millwall eliminated Premier League champions Leicester City with Shaun Cummings scoring a last-minute winner to secure a 1-0 victory for the League One side at The Den.
Leicester were on top in the first half but despite creating a number of chances they were unable to find a way past Jordan Archer, who pulled off two saves to deny Shinji Okazaki on separate occasions.
Millwall were reduced to 10 men shortly after the restart when Jake Cooper was shown a second yellow card for a late tackle on Ahmed Musa, but despite the numerical advantage, Leicester were unable to find a breakthrough with Archer again keeping out Okazaki.
With the game seemingly set for a replay, up popped Cummings in the 90th minute, cutting inside from the right before firing a strike into the bottom corner to win it for Millwall.
Cristhian Stuani scored a late winner for Middlesbrough to secure a 3-2 victory against League One side Oxford United at the Riverside Stadium.
Grant Leadbitter opened the scoring for Boro after 25 minutes, firing a penalty into the roof of the net after Stewart Downing was fouled inside the box by Chris Maguire.
Oxford looked to have equalised in the 32nd minute when Maguire's cross went straight in but the goal was ruled out for a Kane Hemmings foul, before the hosts doubled their lead just two minutes later through a Rudy Gestede bicycle kick after Adama Traore had sent the cross in.
The visitors were back in it when Maguire found the back of the net from a free kick in the 64th minute and, just one minute later, they drew level when Toni Martinez converted a rebound after Maguire had seen his strike saved.
However, Boro had the final say when Stuani fired home after Alvaro Negredo had brought down a cross into the box from Fabio.a