Aston Villa’s back-up crew will be under the spotlight tonight as Martin O’Neill’s men face a key Premier League clash with a rising Sunderland.

The Villa boss could be without three leading performers from the team’s multi-trophy challenging campaign as top scorer Gabby Agbonlahor, defensive kingpin Richard Dunne and midfield ace James Milner all look like missing out.

The trio of stars are struggling against injuries from a conjested season which has brought to the surface Villa’s ability to continue their challenge to Manchester City, Liverpool and Spurs for the fourth place finish that opens the door to the Champions League.

O’Neill marked the build-up to the game engaged in a bout of “expectation management” by insisting City’s sole focus on League results gives the big spenders a vital advantage in the race for fourth.

But with another home game quickly following Saturday’s 2-2 draw with Wolves, which saw O’Neill take issue with some supporter disatisfaction, the Villa boss knows worries about a repeat of the fade-out which fans saw at this stage last season is back on the agenda.

Having been sidelined by a groin injury, a scan at least cleared Agbonlahor of sustaining serious damage to his foot injured in training last week.

But the England international is a doubt along with Milner and Dunne, who is suffering with a sore Achilles.

With an FA Cup semi-final still to come, O’Neill concedes he has to be careful with Milner and Dunne in particular saying: “Those boys have played matches here where they’ve gone through the pain barrier. But the one thing I don’t want to do is jeopardise people’s careers, which I wouldn’t do.

“At this stage of the season it is to be expected that players are feeling injuries and we do have one or two problems.

“We are now coming to the end of March and the season is hotting up. We will probably have to make a few changes over the next couple of games but that must be expected.

“We may have lost a little ground in the league but there are going to be a lot of twists and turns in the remaining games.”

The principle charge against O’Neill from Villa fans who niggled him on Saturday has been his reluctance to turn to the back-up squad at times of trouble but it looks as if he will now have no choice.

One man who is convinced O’Neill’s squad development at Villa is bang on schedule is his opposite number tonight, Steve Bruce.

The Sunderland boss believes Villa have crafted a template for clubs such as his own declaring: “When I first went in at Birmingham we had a chance of overtaking them. But under Martin, with some good investment from the owner and some shrewd management, they have gone from being in the bottom half of the table – which they were for two, three, four years – all of a sudden now to competing in cup finals, semi-finals, competing for the Champions League.

“They have had a magnificent two or three years under Martin and if there are any parallels to be drawn, that’s the example I would love to take.”

With Curtis Davies out of the picture, Carlos Cuellar is expected to move inside to take over from Dunne throwing open the prospect of a return for Luke Young.

* Defender Shane Lowry is set to return to Leeds United on loan until the end of the season. The Villa reserve star’s initial loan spell with the League One promotion chasers was cut short by a knee injury.