Lee Cattermole has not always been regarded as a natural diplomat but, on Saturday evening, Sunderland's captain defused criticism of Martin O'Neill in a manner so disarming that even David Miliband might have been impressed.

As a former foreign secretary, Sunderland's vice-chairman knows all about challenging received wisdom and entrenched opinion; which is precisely the trick Cattermole attempted to pull off.

"This is the best dressing room I've been in during my career," said the midfielder, by some distance O'Neill's best player against Aston Villa. "We've got great team spirit."

His aim was to make those Sunderland supporters, and reporters, who have begun blaming a lack of heart for the team's woeful run of one win in 17 Premier League games since March, one shot on target in three hours and six goals in nine league matches, pause for thought.

The message was that the squad remains behind O'Neill as he faces up to arguably the most testing chapter of an immensely successful managerial career but, unfortunately for Cattermole, not even a politician as accomplished as Miliband could succeed in applying positive spin to Sunderland's plight.

At Middlesbrough Cattermole was part of a dressing room full of creative tension – for a start the captain Gareth Southgate and the manager Steve McClaren did not get on – but that team still reached the Uefa Cup final because they were cleverly coached and possessed players with the mental bravery and imagination to deconstruct opponents.

Perhaps O'Neill is missing the input of the absent John Robertson, the influential coach who accompanied him to previous jobs and maybe a winger-propelled 4-4-2 formation is not right for this particular group.

What is certain is that Sunderland suffer from the lack of a central midfield playmaker alongside Cattermole and that Adam Johnson, Stéphane Sessègnon and James McClean are all having bad cases of the footballers' equivalent of writer's block.

Stephen Ireland and Gabriel Agbonlahor know the feeling but, after the most underwhelming of starts to Paul Lambert's managerial tenure at Villa, both suggested they have emerged, blinking, into the sunlight.

Bolstered by the supportive framework of a 4-2-3-1 system, Ireland – situated in the middle of the attacking midfield three – reminded everyone of why he once ranked as one of the biggest talents in Manchester City's star-studded firmament.

Similarly, Agbonlahor, scorer of the winner following a headed flick-on from the outstanding Christian Benteke, showed off the wonderful counter-attacking acceleration that made him an England international under O'Neill's management at Villa Park.

"Gabriel was excellent," said Lambert whose controversial decisions to drop Darren Bent and Shay Given are beginning to look justifiable. "And Stephen Ireland was exceptional. He's a really clever footballer. We've given him the belief and freedom he needs to use his natural talent to make things happen."

The bad news for O'Neill is that he has no Ireland to slip into central midfield while his love of playing on the break is undermined by Sunderland's shortage of real pace.

Equally damaging is a dearth of emerging bright young things. How O'Neill could do with the equivalents of Villa's Barry Bannan and Ashley Westwood who both excelled in holding roles. The latest product of Crewe Alexandra's academy Westwood looks a particularly exciting prospect.

The same was once said of Johnson but something has gone very wrong. Sunderland's £10m signing seems incapable of assuming the right positions or picking the right pass at the moment.

"After being considered an impact player coming off the bench at City, Adam's been finding playing full games tough going," O'Neill said. "At the moment all the things he's got the ability to do aren't happening but, in the course of time, Adam will be a hit."

With trips to Everton and Fulham followed by home games against West Bromwich and QPR looming, Sunderland's manager could do with Johnson and company defrosting sooner rather than later.

Man of the match Lee Cattermole (Sunderland)