The midfielder has agreed a deal that will keep him at Pittodrie until at least the summer of 2017, much to the relief of manager Derek McInnes.
He feared being forced to sell the player during the forthcoming transfer window if just such an understanding couldn’t be reached with someone whose contract was due to end next May.
Jack would have been able to leave for free at that time and it was a risk McInnes wasn’t willing to take with a player he rates as being at least as valuable as Celtic’s £2 million signing Stuart Armstrong.
Instead, this new arrangement means Aberdeen retain at least a measure of control over the future of a player their manager views as vital if they are to mount a more serious challenge for honours next season.
It’s certainly a mutual appreciation society as the former Scotland Under 21 international insists progress for him and the Dons in just two full seasons under McInnes was a major motivation for staying.
He said: “The manager made it very clear to me that he wanted me to stay and he spoke to me during the season.
“There are a lot of reasons why I signed. For me personally playing European football again is a big thing. The chance to keep doing well with a successful team is a big factor. Also to play under a manager who wants to do his best for the team and the club. We are just at the start under this manager and there is still a lot more to come from us as a team. Hopefully, we can keep progressing year on year.
“The club is on an up so I don’t see why I should leave at this moment. I know that I am still learning the game. Hopefully I can continue to improve. I know the manager will demand that of me.”
McInnes admits persuading Jack to remain at Pittodrie is a major boost to his plans for next season.
The Dons manager added Kenny McLean to the squad last January and Inverness Caley Thistle skipper Graeme Shinnie joins up next month after agreeing a three-year contract at the start of the year.
McInnes is expected to add at least another three players in the summer, including a central defender to replace retiring captain Russell Anderson, but keeping Jack was always a top priority.
McInnes said: “We are all delighted Ryan has committed to the club until the end of season 2016/2017. It shows real intent from Ryan to play his part in a successful Aberdeen team.
“It also demonstrates the club can hold on to its good players as well and, hopefully, Ryan can continue to impress in an Aberdeen shirt next season.”
It has been a productive few days for the Aberdeen manager who also agreed a new one-year contract with veteran midfielder Barry Robson. The former Celtic and Scotland star celebrates his 37th birthday later this year but insists this is no time to retire as, like Jack, he is confident of helping the Pittodrie club claim more silverware next season.
Robson said: “I turn 37 in November and if I can lift another cup it would be a really good achievement and that’s what is in my mind.
“But I wouldn’t play if I didn’t feel as though I could still play first-team football at this level and I am ready to go for another year.”