Guardiola’s side closed the gap on Premier League leaders Liverpool to three points thanks to goals from Raheem Sterling, David Silva and Ilkay Gundogan at the Etihad Stadium.
But City boss Guardiola was frustrated with the way his players struggled to establish any momentum in the first half, just days after they fell behind against Atalanta in the Champions League before eventually winning 5-1.
He fears City will be caught out in future if they continue to play so lethargically in the first half.
“Of course, respect and credit for Aston Villa. The first half we played football but we don’t play in the way we should play,” Guardiola said.
“We were better in the second half. I don’t know if it was because of the early goal.
“In the second we play in the way we normally are but we have to try and play 90 minutes. We played just 45.”
City’s second successive league win means Liverpool are under pressure to beat Tottenham at Anfield in Sunday’s clash between last season’s Champions League finalists.
At the Amex Stadium, Everton blew a 2-1 lead in the final 10 minutes to leave Silva fighting to save his job.
Silva’s side were in trouble after 15 minutes when Pascal Gross smashed a free-kick past Jordan Pickford for his first goal since April.
Everton drew level five minutes later when Richarlison met Lucas Digne’s corner with a header that deflected off Brighton defender Adam Webster into his own net.
Dominic Calvert-Lewin came off the bench to put Everton ahead from Mason Holgate’s pass in the 74th minute.
Silva woes
However, Brighton’s Neal Maupay scored an 80th-minute penalty after Michael Keane was controversially ruled by VAR to have fouled Aaron Connolly.
And Everton defender Digne added to Silva’s woes when his stoppage-time own goal from Leandro Trossard’s cross left Everton two points above the relegation zone after their fifth defeat in their last six league games.
Watford remain bottom of the table after a 0-0 draw against Bournemouth.
The Hornets are still without a league win this season and haven’t won in nine home league games dating back to April.
Lys Mousset finished a memorable week on a high note with the equaliser in Sheffield United’s 1-1 draw at West Ham.
The hosts took the lead in the 44th minute through Robert Snodgrass’s cool finish from Andriy Yarmolenko’s pass.
But Mousset equalised for the Blades in the 69th minute, the French striker netting a fine strike with his first touch after coming off the bench.
After a difficult start following his close-season move from Bournemouth, Mousset now has three goals this term, with two in the last six days following his winner against Arsenal on Monday.
Saturday’s action couldn’t eclipse Leicester’s incredible 9-0 thrashing of Southampton at St Mary’s 24 hours earlier.
The result sent shockwaves through English football and Brendan Rodgers believes there is even better to come from Leicester after they equalled the biggest margin of victory in the Premier League era.
Leicester are third after hat-tricks from Ayoze Perez and Jamie Vardy secured the biggest away win in English top-flight history.
“I think we’ll get better, we will improve. Of course the result and performance is perfect,” Rodgers said.
“We have young players who are only going to gain even more confidence. We will get better. We certainly won’t just be content with what we’re doing.”
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