Guardiola’s side required one point from their match in Piraeus to reach the last-16 and victory on Wednesday ensures they remain firm favourites to finish top of Group C.
City were comfortable throughout against the Greek champions but 20-year-old England international Phil Foden scored the only goal after 36 minutes when he slotted in from Raheem Sterling’s delightful back-pass.
Olympiakos failed to register a shot, or indeed even a touch in City’s box, until the 88th-minute, but Ilkay Gundogan blazed wide and Bernardo Silva was denied at close range as City failed to add to their tally, despite 22 attempts at goal.
“It will come. We would love to do more, but one day it will come and we will break everything,” Guardiola said.
“We played really well in all departments. We are already in the next round, now we can focus on the Premier League and the other competitions.”
Midfielder Kevin de Bruyne was left out of the squad but City welcomed back club record goalscorer Sergio Aguero from injury for the final 13 minutes as they began a spell of 11 games before the end of 2020.
There was a moment of silence prior to kick-off, following news of the death of football legend Diego Maradona at the age of 60.
Foden the difference in one-sided game
City could not have wished for an easier start to their busy end-of-year schedule, but Sterling’s assist for Foden was a rare moment of quality when it mattered in attack.
Foden’s subsequent well-taken finish was his seventh goal involvement in his past 10 appearances in Europe’s elite competition – and he has now been involved in 25 goals in 40 starts for City in all competitions.
Indeed, his 10 goals in all competitions for City in 2020 is – excluding penalties – the most by any Premier League midfielder this calendar year.
Olympiakos offered almost nothing in attack themselves with their two shots arriving in the closing minutes as City’s profligacy offered their opponents hope of an unlikely point.
Four wins from as many group matches, and their 10 goals – as many as they have managed in eight Premier League games – undoubtedly represents a satisfying European campaign to date – one which manager Guardiola said he is “fully optimistic” about.
But, three months on from their painful shock defeat by Lyon at last season’s quarter-final stage, Guardiola can only expect similar wastefulness to be punished deeper into the competition.
City desperate for Aguero return
After slumping to a 2-0 defeat against Tottenham on Saturday, Guardiola said City could not expect Argentine striker Aguero to solve all the problems his side face.
City, 13th in the Premier League and eight points behind leaders Spurs, albeit with a game in hand, have made their worst start since 2008. Typically ruthless under Guardiola, they have not scored more than once in a Premier League game since a 5-2 defeat by Leicester in September.
Despite victory over Olympiakos, this was the latest reminder of how crucial Aguero is to his side.
The 32-year-old returned to the bench at the weekend after a four-game absence, having suffered a hamstring strain against West Ham on 24 October in only his third game since a four-month lay-off due to a knee problem.
Though it has been a different story for City in Europe so far, Aguero’s ability to remain injury-free will be crucial for the battles ahead – beginning with Burnley on Saturday as they look to make up ground in the Premier League.
Guardiola’s perfect group stage record – the stats
- Manchester City have won their opening four games in a Champions League campaign for the second time, also doing so in 2017-18 when they won their first five.
- City manager Pep Guardiola has progressed from the Champions League group stages in all 12 attempts as a coach – the best 100% record of any manager.
- Excluding qualifiers, City have kept three consecutive clean sheets in major European competition for the first time since 1969-70.
- Phil Foden has scored five goals and made two assists in his 10 starts for club and country this season.
- Olympiakos have lost 14 of their last 18 Champions League games and have lost each of their last three without scoring.
Manchester City host Burnley on at 15:00 GMT on Saturday, before travelling to Porto in their penultimate Champions League group game next Tuesday (20:00).