Afterwards Arsène Wenger was able to smile only because Arsenal had clung to an earlier Pires penalty, controversially awarded for a challenge by David James on Henry, and smashed away for a valuable, if unconvincing win that maintains their 100 per cent home record.
Wenger, who watches hundreds of games a year live and from around the world via a giant satellite dish at his home, had never seen anything like the penalty incident either. "Even if you are a long time in football, you are always discovering something new," he said. "That's what makes it so interesting."
Had City snatched an equaliser that would not have flattered them - Darius Vassell was only marginally offside when heading home Joey Barton's cross - Wenger would have been in a less forgiving mood. "I don't think you'll see it happen again at this club," he said.
Henry took the blame for the incident, apologised to the supporters and promised to take all penalties himself from now on.
For Wenger, the incident that became the talking point masked Arsenal's inability to establish a rhythm, rarely troubling James until he conceded the first penalty, the crowd growing restive.
City had looked forward to this match with some confidence. Arsenal, then still without Henry, had just lost at West Bromwich Albion. City in turn, with Andrew Cole scoring twice, had just beaten West Ham at home to reach fourth spot in the table four points ahead of the labouring Gunners. Then suddenly, Henry declared himself fit and Cole's hamstring tightened, leaving City without a cutting edge.
City's impressive young manager Stuart Pearce was magnanimous in defeat, refusing to believe that the penalty manoeuvre was a display of Arsenal arrogance. Pearce has taken a lot of penalties himself. "But before today, I had never seen a penalty that didn't move towards the goal," he said. What if his players had tried a lark like that? "Fine, if they scored," Pearce said. "We'd be having a chat if they didn't."
What bothered him was that City had failed to take something from the match. "This is the third time this season when we haven't got a deserved point," he said. A marginal offside decision robbed City of an equaliser eight minutes after the French farce. They attacked along the right, Barton swung in a cross and Vassell glanced the most delightful header into the roof of the Arsenal net. Unfortunately for City, the linesman's flag was raised.
City have become a more consistent, resilient team under Pearce and were again efficient and tightly organised. They matched Arsenal in midfield, where the teenager Stephen Ireland confirmed his potential after rising swiftly through the ranks at Maine Road. Ireland and Claudio Reyna at the hub of City's midfield rarely gave Cesc Fabregas and Gilberto Silva time to settle and so Arsenal's trademark flowing football was in short supply. Mathieu Flamini and Fabregas are discovering the difference between their old supporting roles and having to be the main men. They are not yet ready for the new demands.
Without Sol Campbell, Ashley Cole, Alexander Hleb, Freddie Ljungberg and Jose Antio Reyes, Arsenal are limping along this season and Saturday's was a stuttering performance enlivened mostly by Henry.
Before the game there was a ceremony with Ian Wright, the former holder of Arsenal's all-time scoring record, presenting a silver cannon to Henry in celebration of the Frenchman passing that total of 185 against Sparta Prague on Tuesday.
Not knowing what to expect, City began uncertainly and should have fallen behind in the 13th minute when Henry broke onto a pass from Lauren. Henry's cross found Pires eight yards out and in front of goal but he blasted the ball high into the North Bank.
After that Arsenal were unconvincing, their aimless football encouraging City not to give up hope. The game changed with Arsenal's first penalty. But it is the second penalty people will remember.
Goal: Pires pen (61) 1-0.
Arsenal (4-4-2): Lehmann; Lauren, Touré, Cygan, Clichy; Fabregas, Flamini, Gilberto,
Pires; Bergkamp, Henry. Substitutes not used: Van Persie, Senderos, Almunia (gk), Owusu-Abeyie, Eboue.
Manchester City (4-4-1-1): James; Mills (Richards, 85), Sommeil, Distin, Jordan; Barton, Ireland, Reyna (Croft, 73), Musampa (Jihai, 85); Vassell; Sibierski. Substitutes not used: Hussein, De Vlieger (gk).
Referee: M Riley (Yorkshire).
Booked: Arsenal Pires, Clichy, Bergkamp; Manchester City Barton, Vassell, Mills, Musampa, Sommeil.
Man of the match: Ireland.