Kyle Walker said Manchester City's performance was "not acceptable" after they missed the opportunity to return to the top of the Premier League with a draw against Nottingham Forest at the City Ground.
Chris Wood's late goal cancelled out Bernardo Silva's rocket from 20 yards, with the visitors missing chances in abundance to put the game to bed.
"We've dropped two points here," said Walker. "The chances we had in front of goal - we need to be better, [with] the calibre of players we've got up front we should be scoring them and putting them away."
Erling Haaland volleyed against the crossbar and ballooned the rebound over the top after Aymeric Laporte's header was brilliantly saved by Forest keeper Keylor Navas.
But Morgan Gibbs-White's fizzed cross was tapped in at the far post in the 84th minute for Wood's first Forest goal.
"I'm not blaming anyone," Walker told Match of the Day. "If the strikers aren't getting the luck or hitting the target, us as a defensive unit need to hang on to the 1-0 victory and secure the three points.
"We know that's not acceptable. That's not me being downbeat but we've set such high standards over the last few years that it should be four or five nil, game done and we move onto the next game."
Forest scored with their only attempt on target, having created four chances to City's 23The draw extended Forest's unbeaten home run to eight games and meant City dropped to second after Arsenal returned to the top with a 4-2 comeback win against Aston Villa earlier on Saturday.
"The hard work we did on Wednesday [in the win against Arsenal], it hasn't gone to waste, but this is a blow because you put that good shift in and play a game that we're not used to with the low percent of possession, so to come here and drop two points is not ideal," Walker said.
"Hopefully there's a few twists and turns in our direction now and we can go and be up there or there abouts to go and win this Premier League."
City rue missed opportunities
After being limited to 37% possession against Arsenal in midweek, the lowest percentage of any Guardiola team in the top flight, City returned to some semblance of normality with a dominant 84% in the opening period on Saturday.
Starting his first game after a spell on the sidelines with a foot injury, Phil Foden was a highlight for City, driving forward and making a nuisance of himself to a depleted Forest backline.
Silva, playing again as a makeshift left-back, sent a decent effort from range whistling over the bar moments before receiving the ball on the edge of the area and firing a stunning left-footed shot into the roof of the net.
The goal was reward for the visitors' continued pressure and they had ample opportunity to prevent the nervy finish, Foden's off-balance pass not quite reaching Haaland for a tap-in and Ilkay Gundogan narrowly misjudging Kyle Walker's cross.
But City, for all their dominance, were made to rue their missed chances and were reduced to last-ditch attempts as they scrambled for a late winner.
Kevin de Bruyne had seven attempts at goal but found his radar to be off target as City failed to capitalise on any momentum gathered from their victory over title rivals Arsenal on Wednesday.
They have now dropped 15 away points this season, compared with 11 in total last term.
"It was a really good game," Guardiola told Match of the Day. "We did everything, we played perfectly, had amazing chances, we were going to see the game out, we couldn't believe it, but this is football. You have to score.
"[It is] one of the best games we've played but we dropped two points."
Forest take their chance
Forest will have considered themselves lucky to go into half-time trailing by only one goal having seen the majority of the first period played in their own half.
They had won four of their past seven matches at home and showed mere glimpses of danger on the counter-attack as City committed bodies forward.
Gibbs-White and Brennan Johnson had chances to break away, with the latter denied by Walker's block before bounding forward again but with no one in support to latch onto his squared ball.
Forest were without centre-backs Scott McKenna and Willy Boly, who picked up injuries last time out, and Steve Cooper's side did not put together any meaningful periods of possession or chances.
But, as City became frustrated, Forest were patient and ultimately efficient enough to take their opportunity when it finally came, their only shot on target all afternoon.
"It is definitely a positive result," said Cooper. "For me, Manchester City are the best team in the world. They are fascinating to watch and study. There was no shame City had the ball as much as they did.
"We rode a bit of luck but we earned a bit of luck with the goal we scored. That was the plan - just to stay in the game and get one moment," he added.
"I owe a lot of gratitude to the players for sticking to the plan."
Player of the match
WoodChris Wood
Nottingham Forest
Squad number39Player nameWood
Squad number15Player nameToffolo
Squad number7Player nameN Williams
Squad number5Player nameMangala
Squad number34Player nameA Ayew
Squad number10Player nameGibbs-White
Squad number20Player nameJohnson
Squad number38Player nameFelipe
Squad number32Player nameRenan Lodi
Squad number6Player nameShelvey
Squad number12Player nameNavas
Squad number28Player nameDanilo
Squad number8Player nameColback
Squad number23Player nameFreuler
Squad number4Player nameWorrall
Squad number24Player nameAurier
Line-ups
Nottm Forest
Formation 4-3-2-1
12Navas
24Aurier4Worrall38Felipe32Lodi
23Freuler6Shelvey8Colback
10Gibbs-White28dos Santos de Oliveira
20Johnson
12Navas24AurierSubstituted forWoodat 79'minutes4WorrallBooked at 14mins38Felipe32LodiSubstituted forToffoloat 79'minutes23Freuler6ShelveySubstituted forMangalaat 72'minutes8ColbackSubstituted forN Williamsat 58'minutes10Gibbs-White28dos Santos de OliveiraSubstituted forA Ayewat 58'minutes20JohnsonSubstitutes
5Mangala7N Williams13Hennessey15Toffolo16Surridge25Dennis31Furtado Scarpa34A Ayew39WoodMan City
Formation 3-2-4-1
31Ederson
14Laporte3Rúben Dias2Walker
20Bernardo Silva16Rodri
8Gündogan17De Bruyne10Grealish47Foden
9Haaland
31Ederson14Laporte3Rúben Dias2Walker20Bernardo Silva16Rodri8Gündogan17De BruyneSubstituted forÁlvarezat 88'minutes10Grealish47FodenSubstituted forAkéat 89'minutes9HaalandSubstitutes
4Phillips6Aké18Ortega19Álvarez21Gómez25Akanji26Mahrez80Palmer82LewisReferee:Graham ScottAttendance:29,365Live Text
Match ends, Nottingham Forest 1, Manchester City 1.
Second Half ends, Nottingham Forest 1, Manchester City 1.
Corner, Manchester City. Conceded by Harry Toffolo.
Attempt blocked. Rúben Dias (Manchester City) header from the centre of the box is blocked. Assisted by Nathan Aké with a cross.
Foul by Aymeric Laporte (Manchester City).
Felipe (Nottingham Forest) wins a free kick in the defensive half.
Substitution, Manchester City. Nathan Aké replaces Phil Foden.
Substitution, Manchester City. Julián Álvarez replaces Kevin De Bruyne.
Foul by Erling Haaland (Manchester City).
Felipe (Nottingham Forest) wins a free kick in the attacking half.
Foul by Bernardo Silva (Manchester City).
Brennan Johnson (Nottingham Forest) wins a free kick in the defensive half.
Attempt blocked. Jack Grealish (Manchester City) right footed shot from outside the box is blocked.
VAR Decision: Goal Nottingham Forest - Nottingham Forest 1-1 Manchester City (Chris Wood).
Goal! Nottingham Forest 1, Manchester City 1. Chris Wood (Nottingham Forest) left footed shot from very close range to the bottom left corner. Assisted by Morgan Gibbs-White.Goal confirmed following VAR Review.
Attempt missed. Kevin De Bruyne (Manchester City) right footed shot from outside the box is too high. Assisted by Jack Grealish.
Jack Grealish (Manchester City) wins a free kick in the defensive half.
Foul by Neco Williams (Nottingham Forest).
Delay over. They are ready to continue.
Substitution, Nottingham Forest. Chris Wood replaces Serge Aurier because of an injury.
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