Speed is of the essence for Norwich City's top brass as they strive to limit the fall-out from David McNally's surprise resignation.

The Canaries need to perform on the pitch to retain any hope of Premier League survival, but chairman Ed Balls insists work is also well under way to replace a key figure in the club's recent history.

'We are going to move as quickly as we can to get a long-term replacement. That is not something you can do in 24 hours,' he said. 'That is something we are actively working on. We had another board meeting on Monday, those meetings will continue over these next few days to make sure we build on the professionalism and strength in the club on the football and non-football side. We have to be ready so that come the day after the end of the season we can face all the normal contractual issues with staff moving forward. If we stay up people will want to know we are in a position to be ready to act in all those areas, and we will and we must.

'If we do go down, and we are still fighting hard until it is not possible to do so, then we have to fight back straight away next season and that means we can not afford to act slowly. We are on the case. We can't afford to lose time in the summer.'

Balls confirmed McNally's successor must have a proven track record in football.

'It is my responsibility, along with the other directors, to make sure we fill this gap and meet the challenges both in the short and long term. We will get the best footballing solution,' he said. 'We need someone to replace David who has deep, long-standing and personal footballing expertise and that is what we are going to do. Delia and Michael asked me to come in to chair the board because I have that sort of experience from politics from being a cabinet minister. My job is to make sure we bring in the right person to take us forward. We all want to do what is right for the football club and we are going to bring in the quality we need.'

Balls made it clear McNally's resignation, in the wake of Norwich's 1-0 Premier League defeat to Manchester United, came totally 'out of the blue'.

'The idea that we would be facing the loss of our chief executive a week before the end of the season and the disruption that causes is not something any of us expected,' he said. 'I wouldn't have chosen the timing, it is not helpful, but you shrug your shoulders and just move forward. We have to deal with it.

'David resigned verbally and then in writing via email and then on Twitter. The board had discussions through Sunday and concluded that we should accept the resignation. All the directors unanimously accepted that. On Saturday none of us expected that to happen. Like the fans we were disappointed because we had lost. It is a matter of huge regret to me, the board and a shock to the fans.

'David made a massive contribution to Norwich City. He put the foundations in place for really strong management at the club. David has been a good servant but he made his decision and we have to respect that.'