There is not a site option or TeamRaiser event option that will automatically disable this.  However, you can remove the verbiage and link that appears on the page after a donor clicks on the Donate button that reads: Search or click here to give directly.
  1. Click Fundraising>TeamRaiser
  2. Click Edit next to your TeamRaiser event
  3. Click Customize Pages from the left navigation bar (step 13)
  4. Click Configure next to Find a Participant
  5. Under the Text Options section, clear out the following fields:
    • Find Button Text: Search
    • Give Directly Text: or click here to give directly
  6. Click Finish