Adlington, who took bronze in Sunday’s 400m freestyle final, is prioritising defending her Beijing gold in the 800m freestyle – although she could still swim in tonight’s final.
And Jackson, who qualified for the final in seventh place along with Caitlin McClatchey, Rebecca Turner and Ellie Faulkner, believes her team are capable of causing an upset against strong competition.
“It's a tough field out there. Thee Americans, the French, the Australians, they're all swimming out of their skin,” said Jackson, who won 400m freestyle bronze in Beijing behind gold medal-winner Adlington.
“They have been amazing here so, just to get amongst it, would be incredible. You never know, relay is just so up and down. So if we get a lane tonight we can give it our best and see what happens.”
Jackson and her team booked their place in the final with 7:54.31 minutes including a team best of 1:57.80mins from Turner to finish fourth in their heat and seventh overall.
McClatchey started proceedings with 1:58.22 mins before Turner took to the pool, then Faulkner swam 1:59.30 mins and Jackson finished with 1:58.80 mins to secure a final spot by just 0.27 seconds.
And 25-year-old Jackson, in her third Olympic campaign, is hoping to feature in the final tonight as Team GB plot a surprise in the pool.
“To stand up there tonight in front of that many people would be incredible. We will just see what happens tonight,” she added.
“Hopefully they (the other finalist) will all be a bit slower and we will be able to sneak in.”