 How many different players did the most high assists on the March 4 game?
CREATE TABLE table_73528 (
    "Game" real,
    "Date" text,
    "Team" text,
    "Score" text,
    "High points" text,
    "High rebounds" text,
    "High assists" text,
    "Location Attendance" text,
    "Record" text
)
SELECT COUNT("High assists") FROM table_73528 WHERE "Date" = 'March 4'