He told BBC Radio Norfolk: "You have to pull out your best, because the strike-force here is quite strong.
"The front three have been magnificent since the start of the season. You have to stay on your game and show why you want to be in the team."
The Canadian frontman failed to find the net in a rare opportunity to lead the line alongside Grant Holt and Wes Hoolahan, with boss Paul Lambert opting to drop Martin after the weekend defeat by Hull City.
I like Jackson and believe he will turn out to be a good signing for us... but I don't see why Martin was dropped as he will no doubt get more chances starting the game than coming off the bench
Competition for a place in the Canaries line-up is at a premium, with Hoolahan making his mark with a brace in mid-week.
"It's good to have that at he club. Hopefully everyone stays on their game and that will put us in the position we want to be next season," Jackson added.
City travel to Bristol City on Saturday after leaping up to third in the Championship table, something Jackson is keen to build on.
"We're flying at the minute, obviously it's early days yet," he said.
"But we're going to keep doing what we're doing. Hopefully pick up wins and see how high we can get."
Source: BBC Sport