De Gea has brushed aside fears over his confidence, insisting he is in top shape and ready to fight Henderson for his starting place.
"I feel very, very well and very confident and very positive and that's very important for me," the Spaniard told manutd.com.
"Now it's time to be back to winning ways and winning trophies, that's the most important thing for us at the moment. Like I say I feel very, very good.
"It's great to train every day here with the coaches and the goalkeepers.
"We always try to learn from each other and try to push altogether. It's great. If you see the training it's really good to see the goalkeepers together.
"It's very important to have good feelings with the other goalkeepers and the goalkeeping coaches as well. It's great.
"We are training, like I say, very, very well – the whole department of keepers. We need to be at this level every day and to show the players that the keepers are feeling 100%. Now like I said we have to go for trophies."