BlackBerry shares fell for the second day in a row after a disappointing US launch for the Z10 saw investment firm Goldman Sachs downgrade its rating for the Canadian firm.
The downgrading comes just days before BlackBerry is set to reveal its key results on Thursday and is unlikely to inspire confidence in the smartphone manufacturer.
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Shares in BlackBerry fell on Nasdaq by almost five per cent to $14.23 (£9.28) by the close of trading in New York yesterday. That followed an almost eight per cent drop in stock value by close of play Friday 22 March, the previous day of trading.
Goldman Sachs described US sales of the BlackBerry Z10 as "tepid", a worrying development for the firm as the bank's analysts have also described the region as being "critical for BlackBerry's ultimate success".
"Our retail checks at over 20 store locations since March 22, including at AT&T, Best Buy and RadioShack, revealed a surprising lack of marketing support and poor positioning of the product," said Goldman Sachs analyst Simona Jankowski, adding "We also saw limited advertising around the launch."
As a result, Goldman Sachs has cut its rating of BlackBerry stock from "buy" to "neutral" - suggesting there's no reason to purchase or sell stock in the firm - and has reduced its estimate of the chances of success for BlackBerry's new devices to 20 per cent, down from 30 per cent.
The drop in share price will come as a blow to BlackBerry, which under its former guise of Research In Motion saw stocks rise to a 13 month high in January. Goldman Sachs upgraded its rating of shares in the firm to "buy" last November.
Despite price cuts since the Z10's British launch in January, BlackBerry's UK and Ireland managing director, Rob Orr, recently claimed all is well with the new product line.
"If you look at the way these guys operate," he told Computing, "they will put short-term offers in place for consumers at different points in time. So it's perfectly normal. I have no feelings whatsoever, quite honestly. Momentum's been great, so there's no complaints."
