Newport's plucky FA Cup run came to an end as two unfortunate mistakes from goalkeeper Joe Day put Manchester City on the way to a hard-fought 4-1 victory in the fifth round at Rodney Parade.

Pep Guardiola named a strong line-up but City's vaunted attackers were frustrated by some resolute defending from their Sky Bet League Two opponents in the opening 45 minutes.

Leroy Sane belatedly broke the deadlock after 51 minutes while Phil Foden struck either side of Padraig Amond pulling one back for Newport before Riyad Mahrez added gloss to the scoreline to put City into the quarter-finals.

After latching on to Gabriel Jesus' pass on the left, Sane unleashed a shot that went straight at Day, who was struck flush in the face and left with a bloody nose before the ball trickled over the line in the 51st minute.

Day's fortunes worsened 15 minutes from time as Foden's low shot squeezed into the net despite the Newport goalkeeper getting a decent hand to the ball.

The home crowd were given something to cheer with two minutes remaining when Amond cheekily lobbed Ederson, but any thoughts of a grandstand finish were quashed when Foden fired into the top corner for his second moments later.

Mahrez then converted after being put through by John Stones to seal a win that looks more comfortable than it was at times.

Ashley Cole scored his first goal in England in more than six years but Derby were eliminated after Brighton held on to secure a 2-1 victory.

The distinguished left-back and seven-time winner of the competition linked up with former Chelsea and England team-mate and now Rams manager Frank Lampard last month, and he managed to get on the score-sheet in only his second appearance for his new club.

Cole, on as a second-half substitute as he continues to build his match fitness, headed home in the 81st minute to score for the first time in his homeland since September 2012.

But it was ultimately in vain as Anthony Knockaert's opener after 33 minutes and Jurgen Locadia's strike in added-on time in the first half secured Brighton's place in the quarter-finals for the second successive season.

Murray Wallace's header after only five minutes proved the difference as Millwall claimed a hard-fought 1-0 victory at AFC Wimbledon.

The League One side had shocked Premier League West Ham in the last round but they were unable to spring another upset as the Lions moved into the quarter-finals for the second time in three seasons.