AT the start of February, Sunderland were sixth in the Premier League. Today, after an eight-game winless run, they are just six points off relegation. Chief Sports Writer Scott Wilson looks at what has gone wrong.

1. Lack of a cutting edge

It is too simplistic to claim that the sale of Darren Bent scuppered Sunderland's season, but it is impossible to deny the club have looked far less potent since the striker joined Aston Villa in January.

The Black Cats have scored nine goals in nine games since Bent departed, but only two of those goals have come from a centre-forward.

Asamoah Gyan clearly has plenty of ability, but Sunderland still haven't worked out how to get the best out of the Ghana international.

Should he be played as a lone striker or alongside another forward? Does he need intricate through balls or crosses from the flank? Is he really a £13m striker anyway?

With Danny Welbeck and Fraizer Campbell both back from injury, Steve Bruce finally has alternative attacking options at his disposal. However, in a closely-fought encounter, he doesn't really have a player to score a goal out of nothing in the manner of Bent.

2. Signings haven't really worked

While Bruce refused to sign a like-for-like replacement for Bent in the January transfer window, he completed two high-profile transfers that were supposed to strengthen Sunderland's squad in the second half of the season. At this stage, it is safe to say that neither has worked out as planned.

Sulley Muntari has failed to reproduce the form he displayed at Inter Milan, and has not even matched the standard of his performances for Portsmouth.

He was an unused substitute at the weekend, and it remains to be seen whether Bruce opts to take up the option of a permanent deal this summer.

Stephane Sessesgnon arrived in a £6.5m transfer on deadline day, but has struggled to adapt to life in the Premier League.

There have been flashes of genuine talent, but the Benin international is hardly the type of player you want in a side scrapping for survival in the bottom half of the table.

3. Too many injuries

Sunderland's injury list has been a cause for concern all season, and while players have been coming back into the squad in the last few weeks, they are unlikely to return to full fitness before the start of next season.

At the back, Michael Turner and Titus Bramble have been particularly badly missed, with John Mensah breaking down at regular intervals.

Lee Cattermole has been absent for large chunks of the season in midfield, while Welbeck and Campbell have also spent significant periods on the sidelines.

With Mensah, Anton Ferdinand and Kieran Richardson all nursing injuries ahead of this weekend's trip to Birmingham, Bruce has pledged to look at his club's medical procedures.

Some of the problems can be attributed to simple bad luck, but if you sign injury-prone players such as Mensah, you have to accept they could be missing for long spells.

4. Too many loan players

While it would be wrong to attribute Sunderland's decline to a lack of effort or commitment, it is worth posing the question of whether a glut of loan players is a barrier to a successful campaign.

Five members of the Black Cats squad are on loan from elsewhere, a figure that is the joint-highest in the league.

The likes of Welbeck, Nedum Onuoha and Ahmed Elmohamady played integral roles as Sunderland pushed towards the European places in the first half of the season.

However, now that the club is battling in the bottom half of the table, is their mindset different to that of a permanent employee who will still be on Wearside next season no matter what?

Welbeck and Onuoha's future has been the subject of considerable conjecture in recent weeks, with neither player expected to sign for Sunderland permanently this summer. Is the temporary nature of their position having a negative effect?

5. Mentally unprepared for a possible relegation battle

Sunderland reached the 37-point mark on January 22. To all intents and purposes, they were safe.

With Birmingham winning the Carling Cup, and Stoke meeting Bolton in an FA Cup semi-final, Europe was ruled out of the equation at an early stage too. So, for the last couple of months, the Black Cats have effectively had nothing to play for.

That's not quite true now of course, as the spectre of relegation has appeared on the horizon, but having subconsciously switched off, are Sunderland's players finding it difficult to turn themselves back on?

Professional footballers should be able to motivate themselves, but while a side like Wigan have been anticipating a relegation battle all season, Sunderland had much loftier ambitions for a while.

Every season, there is one club that tumbles down the table in freefall. As the Black Cats are learning to their cost, once underway, it is hard to arrest the slide.