The sides meet in Lancashire in their quarter-final replay after the initial tie ended goalless at Anfield, with Gary Bowyer's Championship outfit targetting a third Premier League scalp of the season.
While Rovers look set for a mid-table finish in the league, Gestede and King have shone in the FA Cup and former striker Jansen backed the pair to cause Liverpool problems.
Asked whether the duo were likely to be the attacking focal points for Rovers, Jansen told Perform: "You would imagine so, Gestede in particular caused problems at Anfield.
"I watched them against Liverpool and Gestede was a handful for them so I'm sure he'll be a handful at home.
"They did the hard part at Anfield and with Blackburn not having anything to play for at the end of the season, while Liverpool are looking for the Champions League spots, I think it'll mean more to Blackburn on the night.
"I'm sure the crowd will get behind them and it'll be a good one.
"I know what the fans are like down at Ewood and they'll get behind the lads so hopefully they can cause an upset."
Blackburn have beaten Stoke City and Swansea City on their way to the last four.
‘Maybe I’ll be signed by Wrexham, who knows? English football would suit me – if an offer came, I wouldn’t think twice, I’d go immediately’ Euro 2024 cult hero reveals his UK dream
‘Managing Leeds? It was an option that appeared, but it wasn’t the right timing. I decided it wasn’t a good idea to leave the club I was at mid-season’: Premier League boss admits to turning down opportunity to replace Jesse Marsch in 2023
