Postecoglou brought off the struggling Yves Bissouma and Brennan Johnson at half-time against Fulham and sent on Bergvall and Son Heung-min.
The Spurs boss confirmed Bissouma was taken off due to his poor performance, saying: “I just feel Biss can sometimes let the game drift by him.
“He needs to be a little bit more dominant in the way he gets on the ball. At times I think the game gets away from him and today we needed more in that position.
“I needed him to play though, because he hasn’t played a lot. At the same time you’ve got to perform. It’s fair to say, Biss and a few others are probably lacking a bit of confidence.
“That’s affecting him, but we’re at the point of the season now where we need guys to get out there and put…