The away goals rule should count after extra time rather than full-time, says Arsenal manager Arsene Wenger.
His side were eliminated from the Champions League by the rule after drawing 3-3 on aggregate with Monaco.
Arsenal lost 3-1 at home in the first leg on 25 February and went out after winning 2-0 at the Stade Louis II in Tuesday's return.
"The rule was created in the 1960s and the weight of the away goal is too great today," said Wenger.
Away goals only count after extra time in the second leg of League Cup semi-finals, but are applied after 90 minutes in two-legged Champions League and Europa League ties.
They do not count in the Football League play-offs.
Chelsea were also knocked out of the Champions League on away goals and Wenger said the rule was "outdated".
"Two English teams have gone out on away goals and that should be questioned.
"The rule was created in the 1960s to favour attacking teams but football has changed."
Wenger said immediately after Tuesday's second leg that Monaco did not deserve to progress.
Speaking on Thursday, the Frenchman said his team now have to "move on" from their fifth Champions League last-16 elimination in a row.
"We know why we went out - it's down to a dreadful defensive performance in the first leg."
He also said tiredness affected his players following their 3-0 Premier League win over West Ham on Saturday.
"West Ham was a very physical game and we paid for it in the second half of the Monaco game. It's a concern," he added.
Wenger on title race
Arsenal, who travel to Newcastle on Saturday (15:00 GMT), are third in the Premier League, one point behind second-placed Manchester City but seven adrift of leaders Chelsea, who have a game in hand.
"At the moment we are too far away from Chelsea but we have an opportunity every week to get closer," said Wenger.
"We have to continue to improve. We are a better team today than four months ago. We've won 13 of our last 15 games."
Wenger on player behaviour towards referees
After Football Association chairman Greg Dyke expressed concern at the "scary" increase in incidents of players surrounding referees, Wenger said: "We have to respect the referees to make their job as easy as possible. It's difficult for them today as they are criticised a lot."