He's caught 34 passes for 589 yards and five touchdowns, is among the league leaders in each category, and is on pace to set career marks across the board. Jackson, asked if the increased production had more to do with Kelly or him, said it was a combination of both.
"This offseason was a big offseason for myself," Jackson said. "I challenged myself to put on more weight and hit the weights. It's the first year I'm really above weight. . . . At the same time, Chip came in and started a great system for myself to be successful."
For the Eagles to beat the Cowboys on Sunday at Lincoln Financial Field, Jackson will likely have to be an integral part of the offense. The offense wasn't the same in losses to the Chiefs and Broncos. In those games he averaged just 2.5 catches for 48 yards and failed to score.
In years past, it wasn't necessarily a foregone conclusion that the Eagles would lose to the Cowboys if Jackson didn't have a big day. He certainly contributed to victories, like when he caught four passes for 210 yards and a Nestea Plunge touchdown in December 2010.
But in four Eagles wins in which he played, he averaged four catches for 94 yards and had just one touchdown. In five losses, he averaged four catches for 50 yards and had one score.
Kelly seems to have also helped with Jackson suddenly becoming a red zone threat. He has two touchdowns inside the 20 after scoring only five in his first five seasons. Jackson said he's just getting more opportunities.
"In the red zone in the past, they used to take me out and do two tight ends and things like that," Jackson said this week.
Jackson, 26, reached the end zone in a variety of ways during his first three seasons, scoring 17 through the air, three rushing, and four on punt returns. But he had only a total of six touchdowns the next two seasons - all receiving.
He's still used almost exclusively as a receiver, but he's scored from 36, 12, 5, 61, and 25 yards out. Jackson was asked if it bothered him that some considered him only a home-run-hitting player.
"Sometimes it does, because you get taken out of the game and other big receivers get put in the game," he said. "It was just something I kept working with and I figured sooner or later I would get the opportunity."
Jackson has said that he's running a greater variety of routes this season. He's caught 19 passes for 262 yards and three touchdowns over the middle. He's lining up in the slot more than ever. He's running fewer fly routes as a decoy.
Kelly has insisted that his offense is only taking advantage of what defenses give, but there has been an obvious effort to get the ball into the hands of Jackson and running back LeSean McCoy.
"If they are going to try to double somebody and take them away, then we are certainly not going to say, hey, we need to force it in to Player X," Kelly said. "We need to make sure that Player Y, Z, and whomever else can step up and make plays when they get their opportunities."
For the most part, though, Jackson has been the X-factor in getting open.