He shouldn't be rushed back but as soon as he's fit enough he should go straight back in. Some of the more recent clean sheets have been more luck than judgement.
We've only conceded 4 goals (not including the 2 against Juventus when he went off injured) in 12 games with him in the side.
Luck ! The more you practise the luckier you get. You can tell that Ota and MDM are building up a good understanding and the way they celebrated together at the final whistle on Tuesday shows the bond they've built.
If we carry on conceding very few goals I wouldn't change it