Jewell was appointed to the DW Stadium helm in 2001 and oversaw two promotions during his six-year stay to help Latics' elevation to the top flight in 2005, where they remained for nine seasons prior to last May's relegation.
They won the FA Cup - the first major trophy in their history - during that month, though, and played in the Europa League this season while also returning to Wembley for Saturday's FA Cup semi-final, where they only bowed out to Arsenal on penalties.
It has been an incredible journey which Jewell, a Wigan player in the 1980s, can scarcely believe. And he has attributed that meteoric rise to former Blackburn striker Whelan's handling of his home-town club.
"He employs a lot of people in the town, he was a footballer himself and he's put his money where his mouth is," Jewell told Press Association Sport.
"If it weren't for Dave Whelan, Wigan Athletic wouldn't be where they are today. A lot of people have played a big part in it but he is the main man. At his stage of his life he's reaping the benefits now."
Back in December, Owen Coyle was sacked less than six months after he had been appointed with Whelan admitting the two had not seen eye to eye over multiple issues.
Jewell, though, insists his former chairman was not a disruptive influence.
"He just let me get on with it; he was very supportive of me," he added at an event to promote Beko's Keepy-Uppy Challenge.
"It's easy to support a manager when it's going really well. I remember when we lost 5-1 at Wrexham in the Auto Windscreens Shield (in 2001) and they were tough times but he stood by me.
"You sit here now and you look at the FA Cup and that Wigan Athletic have been in the Premier League - hopefully they'll be able to bounce back - it's great not just for Dave Whelan, but the people of Wigan."