The Norwegian centre-back ended any speculation regarding his future by penning a new two-year deal with the Cottagers recently and delighting Jol in the process.
"We are ever so satisfied that he signed his contract because you never know," Jol told reporters. "It was quite challenging trying to keep him.
"I thought I could lose him - and he was a tower of strength this year, last year and before I came here. I always thought he wanted to stay, but you never know.
"He was on a free at the end of the year and it took a long time. But we did everything and in the end it was a happy outcome.
"He came to sign it on Thursday and it was a relief. He is one of the best players in the division, he is our skipper and a very nice man. So, we're very pleased to keep him."