Kelly praised Jackson's ability to get separation with his speed, while also noting there were other ways to get separation, such as by being big and strong enough to outmuscle a press corner. And speed doesn't count for all that much in the red zone, where Jackson is less effective.
Left unsaid was the fact that if the Eagles saw a lot of man coverage last season, it was because teams felt they couldn't handle it effectively. Kelly obviously wants to change that. Though he's only 5-6, Darren Sproles' 71-catch receiving ability was a move in this direction.
"The addition of Sproles, are you gonna play us in man?" Kelly asked. "Now you have to have a linebacker cover him if he's the back. That's kind of a huge addition, when we thought about bringing him in."
How will Kelly use Sproles?
"I don't know," he said. "I'm not being evasive. But until we get out on the field and run around, I know, obviously, he's an outstanding returner and outstanding receiver coming out of backfield. What run plays he runs the best . . . Is he an inside zone guy, is he an outside zone guy? Is power a better play for him? . . . Those are all things we'll figure out when we get our hands on him. But we've got to be smart enough as coaches to get the ball in his hands, because he's a dynamic player with the football in his hands.
Much like former Eagles star Brian Westbrook, Sproles can work from the slot or even on the outside.
"He's got the ability to do that," Kelly agreed, "but again, for us, there's more than, 'Hey, Darren does that well.' How well do we like our no-back protection? When you're in no-back, everybody's thought is, 'Hey, let's rush six and everybody hit your quarterback.' That may be great for Darren, but it may not be great for Nick [Foles]. His versatility and his ability to do different things with him is intriguing."
It would seem the Eagles want to look in this deep draft class for Jackson's replacement. Kelly attended Texas A & M's pro day yesterday, which featured not only Johnny Manziel but projected first-round wideout Mike Evans, 6-5, 231. There's a good chance Evans will be gone when the Eagles pick 22nd overall, though general manager Howie Roseman did note the other day that top wideouts tend to slide a bit on draft day. Roseman also said the wideouts were the strongest position group in the draft.
Kelly wasn't helpful there.
"It's the best draft class of wide receivers since I've been in the league," joked Kelly, who has been in the league 14 months now. "I don't have much to compare it to, but there are some talented players in this draft. When you talk to people, they say it is more talented than it's been in the past."
Whichever receiver the Eagles do end up drafting, there's an excellent chance Kelly will have attended his pro day. Kelly is a pro-day machine; it's not unusual for him to hit several, in different parts of the country, in a week.
"It's another tool in the toolbox, another evaluation," Kelly said. "If the opportunity is there to watch them work out one more time in front of people, why wouldn't you go see them do that? Can't hurt you to have too much information on somebody.
"When you really analyze what goes on at the combine, that's difficult for those guys. They're thrown in there for 3 straight days. They're marching around in their underwear. People are staring at them, poking and prodding them, asking them a million questions. You get a 15-minute interview with them.
"I think when you get a chance to get them back on their campus and get a chance to see them in their environment, you have a better understanding of what they're like as a player and a better feel for who they are. So you're making educated decisions, not just going, 'What about this guy? I don't know. I never met him.'
"It's tough for me to weigh in and say, 'We've got to draft this guy' and jump up on the table for him, based on what? I watched six games and somebody in a report said he was a good kid? I'd rather be a little more hands-on, where I can weigh in when we're having those discussions about how we feel about a player."
On Twitter: @LesBowen