Bangladesh's Mustafizur Rahman is unlikely to play any further part for English county team Sussex this season after he was diagnosed with a tear in his shoulder, cricket officials said Wednesday.

The promising paceman, nicknamed Fizz, aggravated an old shoulder injury during his short stint with Sussex in the ongoing Twenty20 Blast competition, playing two matches and bowling just 7.2 overs before being sidelined.

Sussex rested the 20-year-old left-arm quick from matches against Gloucestershire and Hampshire but hoped he would be fit enough to return for Thursday's clash with Glamorgan.

It had been planned that Mustafizur would join Sussex for the whole of their Blast and One-Day Cup campaigns.

But he only arrived in time to play his first match away to Essex last week.

Sussex said Wednesday that Mustafizur would play no part in their upcoming Blast or One-Day Cup group matches.

"Under the direction of the Bangladesh Cricket Board, (he) is due to have a scan this week to ascertain whether or not he will be fit enough to play in any knockout matches should Sussex qualify for the latter stages of either competition," a club statement said.

"It is hoped that there is a possibility of him returning to Hove in the future."

However, Bangladesh Cricket Board (BCB) spokesman Jalal Yunus said his chance of playing any further matches for Sussex this season looked "very bleak" after an MRI scan suggested a tear in his shoulder.

"We will have another MRI report today to get a full assessment of his conditions," Yunus told reporters in Dhaka.

"But, at the moment I don't see any chance that he will play any further matches for Sussex this season."

Bangladesh national team physio Baizidul Islam said the initial MRI report had detected a Superior Labrum, Anterior to Posterior tear in Mustafizur's shoulder.

"Usually it requires surgery for complete recovery. But players can continue playing with painkillers," he said.

Bangladesh cricketers Tamim Iqbal and Nasir Hossain have suffered similar injuries in the past but continued to play without surgery.

But the BCB's Yunus said that because Mustafizur is a bowler, the board will not take any risks.

"He is a young player with a long future ahead of him. Naturally we would love to get long service from him," said Yunus.

Mustafizur's stint with Sussex was delayed twice over concerns he may be burnt out and visa complications.

He finally joined the county side on July 21, making an instant impact with four against Essex in his debut match in the T20 Blast tournament.

However, he went wicketless against Surrey in his second match.