Amorim replaced Erik ten Hag last November and has since become the fastest manager in the Premier League since 2010 to lose 15 matches, reaching this mark in just 28 games.
United lost 1-0 to Arsenal at Old Trafford in their first Premier League game of the season on Sunday (August 17) thanks to a set piece goal from Riccardo Calafiori.
Despite the result, United fans were upbeat about their side’s performance, and Evra believes they could be a surprise package this season.
Speaking to Stake.com, Evra said: "With United, you never know. One day they make you dream, the next they break your heart.
“But if they get that old fighting spirit back - the one where players bleed for the shirt - they can shock people. It’s about consistency, not Instagram moments.
“Football is a jungle. When results don’t come, the manager is always the first to go. But if you keep changing the chef, the soup will never taste right. Give him time, but at United, time is expensive."