Blake, 31, had been told he would have to wait until after Friday's 2pm Gillette AFL Trade Period deadline to be told if he would be retained, given the club's pursuit of West Coast's key defender Mitch Brown.
But the Brown trade didn't eventuate, and while the Saints will target defenders in the upcoming NAB AFL Draft, Blake has been told he'll be retained.
"He will [get another opportunity]. We rate Jason, obviously he's highly esteemed at the club and we had to wait until the trade period finished to keep all options open, and Jason was aware of that," St Kilda coach Scott Watters told SEN on Friday evening.
"But we've been able to inform him today that he'll remain on the list and he'll have a key role to play next year.
"We'll also go into the draft with some specific targets in that area. We still think there are some players available that can strengthen up that area.
"We also think we have some players on our list that can develop further as well.
"We would have liked Mitch Brown and we certainly worked our butt off to get him but now we move forward and we're still pretty happy with what we've got."
Watters said the Saints were in a position where they "almost held no hand" when it came to the uncontracted Jamie Cripps, who wanted to return to Western Australia.
Cripps was traded to West Coast with NAB AFL Draft pick No.46 for selections 41 and 44.
But, the Saints were unable to obtain Brown, who was seeking a trade home to Victoria and was keen on St Kilda, because a third party - Essendon - wasn't able to contribute.
"When you look at Mitch Brown, the biggest difference is Mitch is under contract," he said.
"Whilst that went right to the wire, and indeed an agreement was in place pending Cale Hooker agreeing to go to West Coast, but unfortunately Cale chose not to go to West Coast and stay at Essendon for one more season.
"If he'd agreed to go to West Coast, a deal would have been done with Mitch."
The Saints were presented with the opportunity to trade for Sydney Swans' small forward Trent Dennis-Lane in the past 24 hours, which Watters said was a boom given he rated him highly.
They also gained Gold Coast ruckman Tom Hickey and tall Claremont forward Tom Lee, as well as draft picks 25, 26, 41 and 44, over the past few weeks.
"We've been able to solve some of the structural concerns we have on our list but not every one," Watters said.
"Sometimes you can't solve every problem in one hit."
Watters also said more had been made of the potential for Farren Ray to leave the Saints than the reality of the situation, and he believed it would have taken an "enormous amount" to get him away from the club.
Jennifer Witham is a reporter for AFL Media. Follow her on Twitter @AFL_JenWitham.
