Complex sentence: His initial position on the field field was central midfielder, but sometimes was playing as a winger or forward... but the most comfortable position he feels playing on, and also the position where he is most efficient is as central midfielder.
Split into simpler sentences: His initial position on the field was a central midfielder, but sometimes he was played as a winger or forward. The most comfortable position he feels playing on, and also the position where he is most efficient is a central midfielder.