JUST days after Sunderland attempted to win over the hearts and minds of a new generation of supporters, a few of the originals could easily have turned their backs on the club after a defeat of catastrophic proportions.

While the cheap seats at the Stadium of Light added nearly 14,000 onto the average gate for last week's Carling Cup tie with Arsenal, easily more than that figure voted with their feet by taking part in an angry walkout as a disorganised Black Cats crumbled against Portsmouth.

Many of those to have taken part in the exodus chose to direct their frustrations at Kelvin Davis, the unfortunate goalkeeper being blamed for three of the four goals conceded by Sunderland on Saturday.

Manager Mick McCarthy is having none of it and insists the embarrassing defeat - the 'most embarrassing 45 minutes he has witnessed' - was a collective thing rather than one man's imperfection.

And, although Davis does hold some responsibility for at least one of the goals, the reaction from certain supporters could well have repercussions on the rest of the season.

If Sunderland are going to drop back down to the Championship, and on the basis of Saturday's second half display they are, then a nervousness of playing in front of their own following will not help.

The Stadium of Light is yet to witness a Sunderland league win since their return to the Premiership and noone at the club could argue with the mass numbers heading for the exit doors with more than 20 minutes remaining.

But barracking Davis, a £1.25m buy from Ipswich, was seen as a bridge too far. "I fully understand people leaving. If I had been in the crowd watching that and seen us go three down, I would have left as well. I couldn't do that because I had to stay and do my job," said McCarthy.

"But by booing Kelvin, they boo me and they boo everybody else. It's not something I like to hear.

"Anyone who blames Kelvin for the third goal (an instinctive 45-yard volley from Matthew Taylor) is looking to blame him. They would probably blame him for the tsunami and anything else disastrous that has happened."

Davis has now conceded ten in his last three games and there are calls for talented, but inexperienced, England under-20 international Ben Alnwick to be given a chance.

Whether McCarthy does decide to take his summer signing out of the firing line before the trip to Arsenal is something for the manager to mull over, but the Sunderland boss does have a point when he suggests the heavy defeat was not all down to Davis.

After such a bright start, when Dean Whitehead stroked in his first goal of the season from the penalty spot inside two minutes, Sunderland's long-awaited home win looked to be on the horizon.

And the non-appearance of the controversial Laurent Robert, when the on loan Newcastle winger claimed to have picked up an injury and refused to make up the numbers on the bench, aided the belief that the three points would stay on Wearside.

But, apart from a stinging 25-yard volley from Whitehead that dropped just wide, Sunderland's attacking play failed to cause the Portsmouth defence any real problems and the slender goal lead was all they could muster at half-time.

Immediately after the break Portsmouth's dreadful first half was quickly forgotten about and manager Alain Perrin, who could have been sacked had they lost, was left to celebrate a second victory of the season.

But even he must have been amazed by the way the scoreline was completely turned around.

Just three minutes after the restart Sunderland's failure to deal with a routine centre from Gregory Vignal allowed Taylor to flick on for Zvonimir Vukic.

Vukic was then afforded the space to take a touch before picking his spot in Davis' far corner.

Even at that point noone could have imagined what lie ahead. But 11 minutes later people were starting to get the picture.

A Dario Silva knock on dropped onto the head of Stubbs, who tried to bring the ball down despite a call from Davis. The pair then contrived to clash into one another, the ball dropped loose and Taylor tapped into an empty net.

Things got worse shortly after. As calls for either side to kick the ball out of play so Silva could receive treatment, Portsmouth kept going and Vukic's flick bounced into Taylor's path 45 yards out.

The exciting midfielder, spotting Davis off his line, struck a perfect volley with the outside of his boot over the Sunderland keeper and into the net. Much to the fans' disgust, with one confronting the Sunderland No 1 inside the penalty area.

And when the whole ground thought things couldn't get any worse Stubbs mis-controlled and gave away the corner which led to a fourth.

After initially clearing, Portsmouth found themselves back in possession and Taylor, from the right, picked out the head of Silva at the back post to complete the rout.

"We're all going to be strong and show our character, we are all going to have to be that way," said McCarthy, whose side to prop up the table again and are five points adrift of Portsmouth.

"We knew full well it would be difficult in this league. Perhaps it's proving harder than we thought. We just have to keep going."

With a trip to Arsenal - who unfortunately for McCarthy can only win at home - next on the agenda for Sunderland, the gap to safety could be six points before they are reunited with their frustrated fans. A victory at Highbury? That would change all that though.

Result: Sunderland 1, Portsmouth 4.

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