The Sunderland midfielder endured a difficult debut in the 3-1 home defeat to Hartlepool on Saturday after being asked to play in an unfamiliar position on the right flank.
While the caretaker Blues boss knows the 21-year-old’s best position is in a central-midfield role, the squad’s lack of depth meant he was asked to do a job for the team elsewhere.
And Whittingham believes it is unfair to make any judgement based on his debut.
‘He should be judged when he is in a position that he likes playing,’ said Whittingham.-
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‘I think he did okay for a guy who was playing out of position somewhat.
‘He can play mostly anywhere in that midfield four and we asked him to play in a position that would have been similar to a wide-right player but also defending a little bit.
‘He obviously hasn’t played there too often and wasn’t quite sure where he was going.
‘But I thanked him for taking that position.
‘He’s a good lad, he’s willing to work and he was willing to go out and play there.’
With Darel Russell having left the club, there is now an opening in central midfield and Whittingham is toying with switching Reed to a more central role for the clash against Notts County tonight.
But Johnny Ertl could also be pushed further forward after struggling in central defence, while Whittingham is also considering a change in formation.
He said: ‘We felt it was the best way to play against Hartlepool and, to a certain extent, it worked when we were on the ball.
‘We know what cost us the game and it was nothing to do with the shape or who was where.
‘If you look at the Hartlepool game, we competed as well as they did. I felt we played better football than they did and created more chances than they did.
‘But it was back to the same old story and conceding from a free-kick that should have been defended better.
‘We did okay with the ball.
‘But I’ve explained to all of the lads that have come here that they have to be aware that they might be asked to play in different positions because you have to do that when you’ve got a small squad and the games come thick and fast.’