Hold One's Nerve Meaning

(idiomatic, intransitive) To stay calm facing nervousness.

Example: 2011 June 28, Piers Newbery, “Wimbledon 2011: Sabine Lisicki beats Marion Bartoli”[1], BBC Sport:
  She held her nerve after failing to serve out the match at the first attempt, seeing three match points slip by in a nervous service game at 6-4 5-4 and recovering from losing the tie-break to dominate the decider.