The Senegal international was bestowed with one of Chelsea's customary long-term agreements upon his arrival from Villarreal last summer, shaking hands on terms on an eight-year deal until 2031.
Jackson endured mixed fortunes in his maiden season at Stamford Bridge, scoring 17 goals and providing six assists in all competitions while being criticised for his wastefulness and lack of discipline.
All throughout the summer window, Chelsea were linked with a surfeit of centre-forwards - namely Napoli's Victor Osimhen - as Armando Broja and Romelu Lukaku headed for the exit door.
However, the window slammed shut without Maresca adding a new number nine to his squad, but Jackson has made a promising start to 2024-25 with three goal contributions from as many Premier League appearances.
Maresca "very happy" with Jackson as new Chelsea contract confirmed
After scoring once and setting up another in the 6-2 demolition of Wolverhampton Wanderers, Jackson opened the scoring in Sunday's clash with Crystal Palace, before Eberechi Eze stole a point for the Eagles.
Despite still having a staggering seven years left to run on his Blues deal, BBC Sport claims that Jackson has now agreed to extend his stay by another two seasons, meaning that he is now tied down to the Blues for the next nine years.
The 23-year-old will therefore be 32 by the time his Chelsea contract expires, and speaking to the media after the game, Maresca confirmed that he had committed himself to the club on a renewal of unknown length.
"The only thing I know is he's signing a new contract - I don't know how many years. I'm very happy," Maresca said of Jackson in his post-match press conference.
"Nicolas is doing a fantastic job with us, on and off the ball. He scored already two goals [this season]. He scored again today. He had another two chances but we are happy with him.
"I have faith, and the club also, even before. Not because we are looking for another striker; not that we don't trust Nicolas. We trust Nicolas. I said last week when the transfer window was still open - he is doing fantastic with us. I am very happy with him."
Jackson receives the Cole Palmer treatment at Chelsea
While most clubs cap their new signings at four or five-year deals - maybe six for a truly special talent - Chelsea's habit of awarding seven or eight-year deals to their fresh faces continues to raise eyebrows and draw criticism from all corners.
However, the Blues will of course argue that such lengthy contracts - and the job security that comes with it - are an indication of how much trust they have in their players, which they hope will be reciprocated to its maximum.
In the case of Cole Palmer - who also recently extended his terms until 2033 - that is certainly the case, and while the jury may still be out on Jackson, his eye-catching start to the new term suggests that Chelsea's decision not to pursue the Osimhen deal in the summer might be vindicated.
The same cannot be said for all of Maresca's troops, though, and Sunday's draw with Palace means that Chelsea have only won two of their first five matches of the new term.