Bristol City boss Lee Johnson warned Manchester City they face a battle to secure their Carabao Cup final place – despite Sergio Aguero's added-time winner.

Aguero headed City's winner in the 92 minute as Pep Guardiola's side came from behind against their Championship opponents to take the advantage at the halfway stage of the tie.

The clubs meet in the return leg at Ashton Gate on January 23 with Johnson warning his side – who have already beaten Watford, Stoke, Crystal Palace and Manchester United – are ready to spring another upset.

“It's not over and everyone needs to know that,” said Johnson. “You heard our fans tonight and there will be 22,000 at Ashton Gate. It's only half time but we're still in this tie.

(Image: AFP)

“I'm very proud of my team, disappointed with the goal late on, but I thought the boys were magnificent.

“Pep Guardiola said to me we've played better than the majority of the Premier League teams that come to Manchester City. We certainly didn't park the bus.”

Show Player

The Robins took the lead a minute before the break when striker Bobby Reid won and converted a penalty after being brought down by City defender John Stones.

City levelled through Kevin De Bruyne 10 minutes after the restart, but were forced to wait right until the final moments to plunder the winner through record goalscorer Aguero.

(Image: AFP/Getty)

(Image: Action Images via Reuters)

(Image: Action Images via Reuters)

Guardiola paid tribute to Bristol City and said: “All credit to Bristol. You can't knock out four teams from the Premier League without being well-organised and having nice players.

“It will be tough in Bristol. We lived that against Huddersfield last season, against Wolves, and if we go to Cardiff [in the FA Cup] it will be so tough.

”The Championship is probably the hardest second division in the world because there are 46 matches and play-offs later, so I have a lot of respect. It's why there are a lot of shocks in the cups.”

(Image: PA)

(Image: AFP/Getty)

(Image: Manchester City FC)

Guardiola also paid tribute to Aguero, who netted his 19 goal of the season. “With Gabriel Jesus not being fit, we have to protect him a bit,” said Guardiola.

“Sergio is on fire, scoring goals again, but always in his career he scores goals. But we create chances.

“We were there a lot if you analyse how many times we shoot, and hopefully in the second leg we can score more goals.”