Kean was handed a deal that will keep him at Blackburn until the summer of 2013, but the club’s new owners Venky’s.
“It is absolutely fantastic news. It gives the team some stability and it is going to be a really exciting time,” Nelsen told Sky Sports News.
“It was a big surprise (Allardyce leaving), but since then the owners have outlined their vision for the club and Steve has stood up and taken a fantastic grip.
“It is a real positive that we are heading in the right direction.”
“At the time it was more confusion because the start of the Christmas period is a very delicate part of the season,” he explained of Allardyce’s exit.
“I think Steve will now want to imprint his DNA on the club and he has already started to do that.
“I think for the rest of the season it will be about stability and hopefully next season we will see a real change.
“He is young and energetic and will do very well as a manager.”