Spark's bad weekend stretched into early morning trading, with the company's stock price dropping 8 cents (1.84 per cent) to $4.27 as soon as the market opened.
The company's share price has since recovered, lifting 6 cents higher than it was on Friday afternoon.
In a note sent out this morning, Craigs Investment Partners said: "It's hard to think of a way to generate more negative press than failing to provide a good experience for an All Black test match".
The investment bank indicated that this could play into the hands of Spark's sport-streaming competitors, Sky TV, whose shares were up 1.75 per cent to $1.16 in early trading.
Over the weekend, Spark was forced to screen the second half of the match between South Africa and the All Blacks on free-to-air TV after many customers faced constant pixelating, blurring, buffering or complete loss of signal.