Lay Down The Marker Meaning

(idiomatic) To set the standard.

Example: 2011 August 7, Chris Bevan, “Man City 2 - 3 Man Utd”[1], BBC Sport:
  City held firm and even threatened to retake the lead when Adam Johnson tested De Gea, but it was United who laid down the marker for the forthcoming Premier League campaign, beginning the defence of their title by collecting more silverware.