LONDON -- The FTSE 100 (INDEX: ^FTSE) had a relatively good week last week but has started this week a little hesitantly, losing 29 points to 5,633 for a 0.5% fall in early trading. The jitters were led by commodities-based companies like the big miners -- Xstrata lost around 2%, and the others weren't far behind -- as we head into an interim reporting season that many fear will be full of doubt.

But one thing that is certain is that whatever the FTSE is doing as a whole, individual companies are going their own ways. Today we look at three members of the FTSE indexes that are having an exceptionally tough time.

JJB Sports (LSE: JJB.L)
When you see JJB Sports in the news, you naturally expect it to be bad, don't you? The shares fell 29% to 7 pence this morning after the sports fashion retailer told us like-for-like sales fell 8% for the 22 weeks to July 1 and that net debt stood at 15.4 million pounds.

Chairman Mike McTighe is also to be replaced by newcomer Robert J. Corliss, who will take the role of deputy chairman until succeeding his new boss on Sept. 1.

The fall has undone most of the recovery that the firm has been making since January, and survival must surely be in the balance again.

Centamin (LSE: CEY.L)
Shares in Centamin slumped by 15% to 62.6 pence in early trading after media in Egypt reported that an unnamed government source had said that the gold miner has breached its concession agreement.

Centamin, for its part, put out a release denying that any such breach has occurred, that it has been given no notice of any such breaches, and that operations at its Sukari mine "continue as normal." Could this be a good time to pick up a bargain priced on ill-founded public fears?

Severfield-Rowen (LSE: SFR.L)
Structural steelmaker Severfield-Rowen lost a further 9% in early trading, dropping 15 pence to 140 pence. This follows a downbeat interim statement in May, which told us that the first half was not going to be great, and then a profit warning in June, in which we learned of more operational cost overruns.

The shares have slumped from a high of 220 pence earlier in the year, and if the second half is better, as the company suggests, could we have an oversold bargain now? The forward dividend yield is looking close to 4%, and there's no sign of it being affected yet -- but there are better dividends out there.

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