If that was not bad enough, five days later he was between the sticks as City romped to a 4-1 derby triumph - and was promptly axed for the next six games.
American Howard insisted: "At times Sir Alex cracks the whip but De Gea's a fantastic keeper, and he'll be fine.
"I keep saying Joe Hart will be one of the best in the world with his natural ability and, mentally, he's so strong. De Gea could be the same, why not?
"He's got every chance, he's got all the tools and he's only a young boy.
"The thing with United is as a goalkeeper you have to be tough.
"The best ones are those who are tough mentally, the ones who bounce back from a drubbing or a mistake.
"They're the ones who can come back from a bad game with a good one and then string another few together.
"Life for a goalkeeper is nearly impossible at the highest level and it's in those moments when the best show what they're made of."