With four goals in his opening seven appearances, Jackson said his striker started the season with "a point to prove". "He was there week in, week out and I didn't feel the team functioned as well without him. So probably partly down to me playing him so much that he had a little bit of a drop off," Jackson told BBC Radio London.
As the play-off semi-final first leg between Wycombe and Charlton finished in a goalless draw, both teams now prepare for a decisive second leg on Thursday.
The EFL, or the English Football League, was first formed back in 1888. Now, some 72 sides compete below the Premier League in the divisions known as the Championship, League One and League Two.