Henderson is competing with De Gea for No1 status after returning from a loan at Sheffield United.
Solskjaer said: "I'm not going to tell you the team today but the goalkeeper training has been fantastic to watch, so enjoyable.
"It's the highest possible quality you can imagine. I know the goalkeeper coaches are enjoying working with them and the stuff they do, some of the stuff is fantastic. It's going to be an interesting thing for many to follow.
"I know it's great to see [Spain coach] Luis Enrique talk about David the way he did after the internationals. Coaches who work with players have got the respect and he shows his respect, when he talks about it being nice if the press talk about what a great goalkeeper we have, but Sergio [Romero] has not come back yet. He's had some extra time."