The Robins put three past West Bromwich Albion without reply to advance to round five, while Pep Guardiola's crop ended Arsenal's hopes of a record-extending 15th crown.
Match preview
As the weather warms up, Nigel Pearson and Bristol City have been walking in a winter wonderland across the FA Cup and Championship, still without defeat since going down 2-0 at home to West Brom in the Boxing Day round of fixtures.
Since that dampening home defeat, Bristol City have gone unbeaten in their last 12 contests in all tournaments - including a replay win over Swansea City in the FA Cup third round before enacting revenge on West Brom on January 28, winning 3-0 in round four courtesy of Sam Bell's brace and an effort from the highly-rated Alex Scott.
Continuing their pattern of reaching the third round then the fifth round in successive seasons - a sequence that they have followed since 2017-18 - Bristol City have not managed to progress to the quarter-finals since all the way back in 1974, losing to Wolverhampton Wanderers and Sheffield United at this stage in 2018-19 and 2020-21 respectively.
Hopes of a playoff charge in the Championship may be slightly far-fetched for the 13th-placed Robins, but the top half remains in sight thanks to a 1-0 victory over Hull City at the weekend, with Nahki Wells coming off the bench to win it from the penalty spot in the 70th minute.
Pearson's side have found the back of the net in all of their 11 fixtures since the turn of the year, and the hosts have also shipped just one goal in their last four at Ashton Gate, but such resilience may prove futile against the Citizens juggernaut.
The more superstitious Man City supporters may not be too despondent with defeat here, as the last team to lose an FA Cup fifth-round tie against Bristol City - Leeds United in 1973-74 - went on to be crowned top-flight champions.
Even though Man City are still playing catch-up to Arsenal in the Premier League, omens will not come into Guardiola's thinking for Tuesday's tie, which the Citizens progressed to thanks to Nathan Ake's striker's finish against the Gunners in the fourth round.
Chelsea have also fallen to the Citizens' superiority in the FA Cup this season, but Guardiola only has the 2018-19 trophy in his cabinet from his time in charge so far - witnessing his side suffer semi-final heartache in each of the last three seasons.
Fifth-round exits to lower-tier opposition is not a novelty to Guardiola either - Wigan Athletic stunned Man City at this point in the 2017-18 tournament - but a trip south to face Bournemouth at the weekend ended in a comprehensive 4-1 success, despite the Cherries' spirited showing.
Cutting Arsenal's lead at the top of the Premier League table back down to two points having played a game more, next on the agenda for Man City is avoiding a first defeat to Bristol City in 44 years, although a 5-3 aggregate success against the Robins in the 2017-18 EFL Cup semi-finals was far from straightforward.
Bristol City FA Cup form:
D
W
W
Bristol City form (all competitions):
W
W
W
D
D
W
Manchester City FA Cup form:
W
W
Manchester City form (all competitions):
L
W
W
D
D
W
Team News
Earlier this month, it was confirmed that defender Rob Atkinson would miss the rest of the campaign due to a cruciate ligament rupture, and he is the second Robins player to suffer that fate this season after Ayman Benarous.
Kal Naismith, Kane Wilson and Tommy Conway will not be at Pearson's disposal either, but Bristol City have no fresh concerns to report from the weekend. Harry Cornick and Anis Mehmeti are both cup-tied, though.
With ex-Wycombe Wanderers man Mehmeti absent, Wells can expect an immediate recall to the hosts' first XI as Sam Bell reverts to a wide role, while 19-year-old Scott should act as creator-in-chief amid links with several top Premier League teams.
As for Man City, Guardiola could potentially welcome Aymeric Laporte back from illness for the fifth-round clash, but John Stones's thigh injury is unlikely to heal in time.
The infamous 'Pep roulette' should come into play as the visiting coach rotates his resources, with Stefan Ortega, Kalvin Phillips, Sergio Gomez and potentially even Maximo Perrone forcing their way in.
Kevin De Bruyne was restricted to a bench-warming evening against Bournemouth after recovering from illness, and Guardiola should be reluctant to throw the Belgian in from the first whistle here too.
Bristol City possible starting lineup:
O'Leary; Tanner, Vyner, Kalas, Pring; James, Williams; Sykes, Scott, Bell; Wells
Manchester City possible starting lineup:
Ortega; Lewis, Dias, Ake, Gomez; Silva, Phillips, Gundogan; Mahrez, Alvarez, Foden
We say: Bristol City 0-3 Manchester City
Bristol City's period of preparation for a meeting with the Premier League champions could hardly have gone any better, but any hopes of the Robins extending their unbeaten run here are surely unfounded.