The Portuguese hosts led PSV 3-2 at the break after Kuca and Diogo Amado had scored in the final 15 minutes of the opening half on Thursday.
However, heavy rain started to fall at half-time and the players never returned to the pitch.
UEFA announced the game had been abandoned at 23:00 local time (23:00 GMT).
A statement on the governing body's official website read: "Due to the weather conditions, and the resulting unsuitable pitch conditions, the referee, in conjunction with the UEFA delegate, has decided to abandon the match between Estoril and PSV before the start of the second half.
"The game will be finished at 17:00 CET [16:00 GMT] on Friday."
If Estoril win they will rise to within a point of second-placed PSV in Group E ahead of the final matchday, while leaders Dinamo Moscow have already secured a spot in the knockout stages.