MICK McCarthy has highlighted Everton's dramatic decline as evidence of the way in which Premiership fortunes can be turned upside down.

At the start of the season, Everton were a disallowed goal away from the group stage of the Champions League following May's impressive fourth-placed finish in the Premiership.

Four months on, though, and it is a very different story. David Moyes' side will arrive at the Stadium of Light this afternoon just three points clear of the drop zone and, following Wednesday's disastrous derby defeat to Liverpool, even their manager's position is in jeopardy.

In many ways, it has been a similar story on Wearside. The euphoria of last season's Championship success has been washed away by a plethora of defeats that have cast the Black Cats adrift at the foot of the Premiership.

Yet, just as the two clubs' downward trajectory has proved difficult to reverse, so an upward momentum could prove similarly unstoppable should things fall into place in the second half of the season.

All that is needed is a catalyst, something to change the prevailing mood and kick-start a chain reaction that could quickly turn into a lengthy unbeaten run.

According to McCarthy, that catalyst could be a win against Everton, with Monday's goalless draw against Bolton laying the foundations for a radical reversal in fortune.

"Certain incidents happen that shape an entire season," said the Black Cats boss, who will name an unchanged side for this afternoon's game following Wednesday night's postponement at Blackburn. "Sometimes it's for the good, and sometimes it's for the bad.

"I think failing to get into the Champions League has had a profound effect on Everton. I watched them against Villarreal (in the qualifying round) and, for 25 minutes, they battered them.

"But they had a goal disallowed that would have got them into the Champions League. If that had gone in, they would probably have been rocking and rolling by now.

"Instead, they got one or two slaps early on like we did and it knocked their confidence. Things like that knock your performances entirely.

"Events during a season really do take their toll, both on an individual and on the team. There are occasions when you have done well, but you get a knock-back and it knocks the stuffing out of you.

"On the flip-side of that, though, you might get a lucky decision, or a lucky 1-0 win and, all of a sudden, you get a massive lift. Suddenly you're flying and the whole place is buzzing.

"We had a good result on Monday, and a good performance, and you could sense it there and then.

"As far as I'm concerned, this is a start. I viewed the Bolton game as a fresh start for us because we can do nothing about what has gone before. It is up to us now to keep that going and turn things around."

Monday's spirited showing against Bolton could indeed turn out to have been a turning point in an otherwise calamitous campaign. On the other hand, though, it could prove to have been nothing more than another false dawn.

In late September, Sunderland went three games undefeated and looked to have finally come to terms with the rigours of the Premiership.

A subsequent nine-game losing run quickly dispelled that theory and McCarthy is sensible enough to admit that this week's limited success will count for nothing if his side fail to beat one of their leading relegation rivals this afternoon.

"We had to start afresh," said the Yorkshireman. "We picked up a point against a very good team on Boxing Day and no-one will have given us a chance of getting anything out of that game.

"We played very well but we must build on that performance. We want, no, we need three points. We need to string a run of results together if we are to move up the table and be part of the shake-up at the end."

For that to happen, Sunderland require the same defensive resolve that earned only a second clean sheet of the season five days ago.

Prior to the visit of Bolton, the Black Cats had shipped 18 goals in their previous seven games, a tally that largely explained their lengthy losing run.

Defenders who had looked calm and composed in the Championship suddenly started making elementary errors, while summer signings brought in to strengthen the backline have only succeeded in exacerbating the problem.

Understandably, McCarthy is reluctant to pin all of the blame on his defence and, after a much tighter showing on Boxing Day, the Black Cats boss is looking for further all-round improvement this afternoon.

"We have been involved in too many high-scoring games," he explained. "If you went through our back-four, anyone who has played at any stage will have come in for some criticism.

"We have conceded so many goals that everyone who has played - whether it be the goalkeeper, right-back, left-back or the centre-backs - will have been involved in something that has caused us a problem or cost us a goal.

"They are not happy about it or proud about it, but they have kept on going and competing. Individually, and as a unit against Bolton, I thought they were all very good. They worked hard at it and put a shift in.

"Anyway, I worry when people knock the defence because there are six players in front of them who are also responsible for defending. As a team, all over the pitch, they need to be working as hard as they can."

Sunderland: Davis, Hoyte, Breen, Caldwell, D.Collins, Lawrence, Bassila, Whitehead, Arca, Gray, Stead. Subs (from): Alnwick, Le Tallec, Nosworthy, Murphy, Woods.

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