Arsenal celebrated in unison as Danny Welbeck's strike earned a 1-0 win which leaves Norwich's Premier League position ever more precarious.
The well-publicised protests in the 12th and 78th minute - to signal 12 years since Arsenal's last Premier League title - were a bit like the Gunners' season. Lots of expectation, poor execution.
And Welbeck gave Arsene Wenger reason for cheer and optimism of an 18th successive season in the Champions League with the decisive goal.
The Gunners' clash at Manchester City on May 8 will be crucial in determining their finishing position, while Norwich play at home to Manchester United the previous day desperate for points in their bid to avoid the drop.
A small minority took part in the protests and were shouted down by pro-Wenger chants. Arguments even broke out between rival factions.
There may have been greater agreement had the "Time for change" posters been directed at Giroud, Arsenal's number 12, so abject was his performance.
And the decision to send on Welbeck for Alex Iwobi, instead of the Frenchman, was jeered.
It was soon justified. Giroud met Hector Bellerin's cross with a cushioned header which Welbeck drilled into the corner, three minutes after his introduction.
Norwich are still without a win at Arsenal since the opening day of the inaugural Premier League season in August 1992. They have won two of their last 15 league games, with 11 defeats.