"Only" needs to be as close as possible in the sentence to the word that it modifies. The placement affects your meaning.

Only team members can play on the field.
(You can play on the field if you're a member of the team. If you're not, find somewhere else to play.)

Team members can only play on the field.
(Team members can't run, dance, or sing on the field.)

Team members can play only on the field.
(Team members can't play in the street, front yard, or Yankee Stadium."