Nicky Smith scored the only try of the match when he bundled over from close range on his 50th appearance for the club.
But Jackson was at his best off the tee and he kicked three penalties in an attritional affair to help his side keep their 100 per cent record at the start of the new season.
And head coach Tandy believes Ospreys deserved more from a physical encounter.
"We're disappointed that we didn't see the game out" he said.
"We deserved more than just a point from this game. In the changing room it's a feeling of disappointment.
"I feel we could have done more ourselves to see that game out.
"It was a huge, huge effort and every one of the team deserve credit for the way they approached the task and stuck at it, but the ultimate feeling for us all tonight has to be disappointment and frustration.
"It's a frustrated group, after the effort they've put in to come away with just a point.
"There's a huge game coming up now at the Liberty next weekend against the Blues and that has to be the focus.
"Hopefully, at the back end of the season we'll look at this as a good point gained but right now it's bitterly disappointing as we thought we did enough to win the game."