Was this the day Norwich City came of age?

As metaphors go, the irony would surely not have been lost on Paul Lambert. The Scot shook Chelsea counterpart Andre Villas-Boas by the hand – warmer than the post-match verbal barbs to come perhaps suggested – and then ventured five yards onto the playing surface.

There he stood. Hands on hips. Scarcely able to comprehend how a performance of courage, self belief and determination from his men had unravelled into a first Premier League defeat of the season.

The platitudes and compliments coming City's way as a result will mean little to Lambert. The Scot is a pragmatist. The only currency he deals in is Premier League points.

But, even this early in the proceedings, the Norwich manager had just presided over a coming-of-age display. Lambert demanded a fearless performance. He got one.

Jose Bosingwa was given too much time and space on the edge of the Norwich penalty box inside the opening six minutes. The finish from the Portuguese international defender was sublime as his long-range strike arced away from John Ruddy before veering inside the City keeper's right-hand post.

This wasn't Carrow Road – save a vocal but small sample of the Norfolk Nation transported to a corner of the famous Shed End. There was no 25,000-plus home crowd to pick up the men in green and yellow, to lift spirits. To drive them on to greater heights.

This was West London. Facing a club with one of the best home records in English top-flight football during the past decade. As one of the banners draped at the opposite end of the ground proclaimed, Norwich had entered 'Roman's Empire'.

City's attacking boldness for the rest of the first half shook the foundations. Grant Holt's first Premier League goal just past the hour mark sent tremors rippling around the stadium.

The immaculately-tailored Villas-Boas removed the suit jacket. The calm, studied exterior on the first whistle had been replaced by a crouching, haunched figure at the front of the home technical area.

The 33-year-old still looked coolness personified, but the rumblings of discontent as Chelsea's superstars over-hit pass after pass or miscued another cross appeared to have transmitted itself to the captain of the ship.

Anyone connected with the Canaries was under no illusions at the size of the task. Chelsea's owner reportedly wrote out a cheque for a shade over �13m in compensation this summer to relieve Porto of their bright young thing. Considerably more than Lambert lavished on his six new playing recruits – allied to the loan arrivals of Ritchie De Laet and Kyle Naughton.

The home fans officially welcomed Juan Mata and Romelu Lukaku prior to kick off. Two more bright young things. Another sizeable flow of money departing Roman Abramovich's bank account.

The financial gulf is vast. But for 90 minutes – and the large slice of stoppage time that followed Didier Drogba's horrendous second–half collision with Ruddy – Norwich were full value.

The names on the opposition team sheet may not carry the cache of the blue chip Chelsea throughbreds – every member of the home starting line-up was a full international – but Lambert and his players care little for reputations.

Grant Holt has taken the B-roads to the top. Playing against the England captain in front of 40,000 punters and global television audiences are a long way from Workington on a wet Wednesday. City's skipper introduced himself to John Terry with a pre-match obligatory hand shake. Then a gentle shove which lifted 'JT' off his feet as he tried to hurdle Hilario inside the opening minutes.

The subliminal message was loud and clear; Norwich were not in the capital on a tourist trip. Whatever Chelsea mined from this particular afternoon was going to be earned. Hard earned.

Things got worse before they got better after Bosingwa's early dagger. Zak Whitbread returned to terra firma following a mid-air duel with Drogba and immediately signalled to the bench. Lambert turned away to slap his seat in pure frustration. In the heat of battle, the potential longer-term repercussions were painfully clear, with Elliott Ward and Dani Ayala already sidelined.

Anthony Pilkington entered the fray for the American. Another message in itself. The wing back system was ditched in favour of the diamond. The alteration did little to check Naughton's spirit of adventure.

The Tottenham loanee looked made for this sort of stage. Faced with one of the best full-backs in the modern game in the shape of Ashley Cole on the same flank, Naughton was every bit his equal.

The youngster controlled Bradley Johnson's raking crossfield ball before a weighted pass into Wes Hoolahan whose cross just dipped behind the advancing Holt. The first stirrings of resistance.

Naughton advanced into enemy territory to hammer a shot that deflected behind after brushing Terry. Hoolahan slipped in Chris Martin who scuffed at Hilario. The ball spat backwards towards Naughton who controlled it instantly before unleashing a half volley Hilario did well to tip over.

Lambert was living every moment on the touchline. Hands were thrust to head again when Holt's cushioned flick dropped at Hilario's feet. There was almost a surreal quality to Norwich's impudence – the temerity to press genuine Premier League title challengers back on their own manor.

City looked dangerous in attack, arguably to a greater degree than the two previous league outings against the considerably less-heralded Wigan and Stoke. Defensively resolute. Despite Whitbread's unscheduled exit.

Fernando Torres lined up De Laet on the edge of the Norwich box. Torres at his imperious Liverpool best spelt danger. But the explosive initial surge is as absent as the killer instinct in front of goal these days. De Laet rolled with the body movement and produced a wonderfully precise interception.

The Belgian was later to blot his own copybook deep in stoppage time with a blind back pass seized on by the hugely impressive Mata. Nevertheless, the 20-year-old has already shown enough in the opening weeks to prove his undoubted quality will flourish over the full course and distance this season.

Half-time did little to alter the dynamic. Chelsea emerged intent on wrestling back the initiative. Hilario and Branislav Ivanovic merely combined to hasten their manager's costume change. Holt hooked the dropping ball back over his head into an empty net then raced away to take the acclaim.

Many may have settled for a third consecutive score draw. Not Lambert. The recently-introduced Steve Morison burst onto Holt's pass. The difference between the Championship and the Premier League was all the time it took Terry to race back and intervene.

City's attacking ambition ultimately proved their downfall. Nicolas Anelka gathered a clearance from the visitors' corner to supply Ramires. The Brazilian clipped the ball away a split second before Ruddy arrived. It was the big man's last act.

Frank Lampard slotted the penalty, once order had been restored between the respective coaching teams on the touchline after a minor spat sparked by an unwanted incursion from Chelsea's fitness coach into the away technical area.

City still threatened in the remaining seconds of normal time when Morison chipped over with Holt unmarked at the back post. Ivanovic should have added a third from close range. Mata did when De Laet's reverse pass was suitably punished deep into 11 minutes of added on time. It was cruel, but it was merely a footnote on a performance to remember for the Canaries.

Villas-Boas had been able to turn around and motion to a World and European Championship winner to get stripped for action with the game hanging in the balance. A precociously talented young midfield maestro who was the fulcrum of his country's U21 European Championship success earlier this summer. With a price tag to match.

The financial gulf may well be vast. But City on this evidence proved they can bridge the gap.