lose ground

(idiomatic) To suffer loss or disadvantage; to experience a setback.

Example:   He lost ground in his career due to his illness.
  The are losing ground to foreign competitors every year.
2014 November 14, Stephen Halliday, “Scotland 1-0 Republic of Ireland: Maloney the hero”[1], The Scotsman:
  The pre-match mantra from the Scotland camp may have been of it not being a “must win” game but that fooled no-one, Poland’s win in Georgia earlier last night simply crystallised how vital it was for the Scots not to lose any more ground at this stage of an intensely competitive campaign.