Phil Smith: Sunderland's FA Cup approach was tough to watch - they let their fans down at Port Vale

Had Sunderland needed a reminder of what the FA Cup still means to their supporters, they needed only to glance at the sold-out away end at Vale Park.

Many of those 3,000 or so would have travelled through the night to make it to Bournemouth just a week previous, and moved heaven and earth to make sure they could be at Leeds on Tuesday. With just four days notice, here they were again and strong not just in numbers but in voice: there was an energy behind the goal in those opening minutes that reflected the opportunity ahead and the sense that a proper cup run has been a long time coming.

For the best part of a decade now and perhaps even longer, Sunderland fans have consistently had to put up with the cup being pushed to the bottom of the agenda. There's not really been much choice but to accept it because the obvious importance of promotion first from League One and then the Championship, combined with the unlikelihood of making it to the last four with those squads, has meant that it's hard to argue against a pragmatic approach. What was so bitterly disappointing about this afternoon in Burslem is that previously, it had looked like Sunderland shared the view of their fanbase that this year could be different. The schedule between now and the end of the season is forgiving and even if Sunderland still have much to do in the Premier League, their primary objective is all but achieved. Régis Le Bris's selection and the performance of his side in the previous two rounds has been refreshing, a team and staff seemingly determined to grasp the moment. There was always the danger of drawing a Manchester City or an Arsenal away somewhere done the line, and maybe that would have been that for another year. But what if you don't? Why not give it a go, and hope for a little bit of luck along the way?

It makes Sunderland's utterly insipid fifth round showing all the more difficult to understand and to accept. Yes, the pitch was abysmal and yes, many of the same XI here had expended a lot of energy in battling performances at Bournemouth and Leeds that had rightly earned praise across the board. Yes, Le Bris is facing a mini injury crisis and had very little senior experience on the bench. None of that, though, can explain away the lack of intensity Sunderland brought to this game or how long it took them to react to the painfully obvious fact that they were on the way to being knocked out..

In the final fifteen minutes or so there seemed to be a belated realisation that the game was getting away from them, and a tactical switch that finally brought a little more presence in the final third and reflected the fact that this wasn't going to be a game won though passing patters in the middle of the pitch. Sunderland at least tried to move the ball a bit quicker, to pack the box and put the Port Vale defence under pressure. Their quality deserted them, however, and the hosts were genuinely deserving winners. Not just because of their spirit in upsetting the odds, but because their application and approach to the game was superior. They didn't just sit ten players behind the ball and hope for the best, but left pace and numbers up the pitch to ensure they could maintain a threat on the break to keep Sunderland honest. This was no smash-and-grab, on balance of play it was a deserved win even if Sunderland spurned a couple of decent openings from set plays. Referee Anthony Taylor was right not to send off Melker Ellborg for a challenge on substitute George Hall in the second half, but it was another move that reflected Port Vale's status as the more incisive team even with less possession.

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Le Bris rejected the suggestion his players had been complacent after the game, instead stating his view that they had struggled to 'reset' for the challenge after two difficult Premier League away games. Did this loss hurt as much as it should have done? For many, that will be the question left hanging in the air as the dust settles on this woeful day in an otherwise excellent season.

Losing doesn't change how quickly this team have progressed or what they have given the club and its supporters over the year. With key players potentially returning from injury this week, there's still every chance Sunderland finish the campaign strongly and make this one of the best seasons in the club's modern history. The frustration will linger, though. It will sting again when the draw is made on Monday night, and it sinks in that Sunderland have blown the chance to go potentially one home win away from Wembley. It will most certainly sting again when Sunderland have an enforced three-week break after the Tyne-Wear derby, a game which now has even greater importance. The FA Cup might not be Sunderland's number one priority, but it matters to fans and we have seen too many times how quickly a poor defeat can take momentum out of a campaign. This year, it felt like maybe that lesson had been learned but the performance suggested otherwise. This has been an amazing time to follow Sunderland, which only serves to underline just how big a chance was missed here.

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