MARTIN O'NEILL is concerned about Sunderland's paucity in attack, but is confident that his side can be firing on all cylinders against Wigan Athletic today.

Steven Fletcher is the only Black Cat to score in the Premier League this season, hitting four goals from precisely four chances, while Sunderland have averaged a Premier League-low of five shots on target per game.

However, O'Neill knows that it is early days, and while he is confident that Fletcher is more than able to carry the pressure, he would like to see his team weigh in with more chances and goals.

"It is a concern. We need to improve and we are capable of doing that," said the Sunderland manager. "I wouldn't want to wish that [expectation on Fletcher] on anyone for the whole of the season.

"Steven's an excellent finisher, he's had a great start to his career here, it makes it easier to settle in.

"But eventually we would need other players to score goals, but making assessments after four games is a wee bit rash.

"It is too early to make massive judgments on how the season is going after only four games and four draws. It would have been nice to have held on against West Ham and Swansea and Liverpool but we have played some decent stuff.

"We played Swansea when they were unbeaten and at the top of their group, so the opposition has not by any means been easy.

"We are what we are and if we win a game I'll be delighted and the sooner the better.

"It will be tough for us, Wigan are capable of winning away from home in this league. They won't come in fear of us but we have just got to get the crowd behind us and go for it."

Adam Johnson will be handed a fitness test as he continues to struggle with a thigh injury, and O'Neill admits that the England winger's career on Wearside has not properly started yet.

"It has been really frustrating," said the Northern Irishman.

"He came back with injury from England, we thought it might clear up and it hasn't seem to do so."

While a late decision will be taken on Johnson, O'Neill's main headache in the run-up to this afternoon's fixture is in the centre of midfield following the suspension of Lee Cattermole after his sending-off at MK Dons on Tuesday night.

The Sunderland manager will consider shaking up the formation after admitting that he does not believe there is anyone else capable of performing the same role as his captain.

He said: "I don't think that at the minute we have anybody who can do that role. We can change things round, but we don't really have anyone.

"There's always a possibility of players coming up who you might not have initially thought of.

"Also, if Phil Bardsley can come back in the not too distant future, it gives a chance for Craig [Gardner] to go back to his normal position. You never know with the injuries, you start to think about things a week in advance.

"Craig has played every game this season at right back when he is essentially a midfielder. You have to make do. It doesn't matter, we're not the only club."