Valletta dropped two vital points as they were held in a goalless draw by St. Andrews at the Victor Tedesco Stadium on Friday.
It was a highly disappointing result for the Citizens in their bid not to lose further ground with leaders Balzan and second-placed Birkirkara.
On Saturday Balzan, three points clear at top take on Tarxien Rainbows.
Second placed B’Kara face a strong challenge from Hibernians on Sunday.
The weekend fixtures may face disruption as strong winds and heavy rains lash the island.
