You don't put pressure on your only choice goalkeeper like, it's asking for trouble for a player with that little experience, in his circumstances, in that position and at his age. It's plain dumb.
Funnily enough, I remember Redknapp doing the exact same thing with Ben Alnwick at Spurs just before a game at Old Trafford (think it was in the cup).
Gomes and Cudicini(?) were injured, so was the fourth choice, and he was the only fit keeper. Redknapp's quotes when asked about whether he was confident in him were along the lines of "Well, he's my only goalie, so I'll have to go with him. I don't have a choice. I don't have another goalie to play."