Newcastle United were beaten 3-0 by Leicester City at the weekend.
Wijnaldum started the match in his familiar left-wing berth, but an injury to Cheick Tiote forced him to play a more central role.
And the Dutch international midfielder admits that he struggled to make an impact from central midfield, with his performance falling below his usual standards.
"It is difficult. First half I played on the left side and I was free to walk where I want," he said.
“Because of the injury to Cheicky I had to move inside more. It is not like I can’t play there but it is difficult for me because I have the quality to make goals in an advanced person.
“If a manager wants you to play in a position you play there.”
Wijnaldum has been one of Newcastle’s success stories of the summer transfer window, with his initial displays impressive.
However, the powerful midfielder was way off the pace against Leicester, like many of his teammates.
Leicester ran out 3-0 winners at St. James’ Park on Saturday, inflicting further misery on McClaren’s side, and destroying any momentum that they had built up.
Newcastle are now just one point clear of the drop-zone, with their next match coming against Crystal Palace.