When Eagles coach Doug Pederson spoke with reporters on Monday, Pederson's trade deadline message was that he liked his roster, and that the organization would have to be very careful not to disrupt the all-for-one, one-for-all locker-room mojo built during the Birds' 7-1 start.

"It would have to be a pretty special fit to make it work," Pederson said.

A little more than 24 hours later, as the 4 p.m. NFL trade deadline loomed, Eagles vice president Howie Roseman stood at the same NovaCare lectern and welcomed Pro Bowl running back Jay Ajayi to the fold.

Special? Well, Ajayi ran for 1,272 yards on 260 carries last season, including an NFL-best average of 3.5 yards after contact per attempt, according to Pro Football Focus.

Fit? There it gets tricky. The Eagles now employ five running backs, led by LeGarrette Blount (100 carries, 467 yards), who had every reason to think he would continue to be the lead back for the second half of the season. Roseman spoke to Blount before the team announced the trade, and told reporters that Blount "continues to be our starter," before being asked a follow-up to that and conceding "that's really up to the coaches."

Asked Blount's reaction to the news, Roseman said: "LeGarrette's awesome. He wants to win. He's won. He's all about winning. He's been in situations before where there have been [other] productive backs on the team. He's been a tremendous team guy since he's walked in the building and a leader for this football team. Nothing changed today."

Even if nothing changed regarding Blount's focus, something did change – the Eagles added a prime weapon for Carson Wentz, and that weapon was available to them at least partly because Miami coach Adam Gase hasn't been happy with Ajayi's attitude. The Miami Herald cited "locker room chemistry and player buy-in" as reasons why the Dolphins were so willing to part with a 24-year-old lead back coming off a Pro Bowl season.

Ajayi, left off a team flight early last season, reportedly was unhappy when he didn't get the ball enough, even in wins. A few days ago, in the aftermath of a 40-0 loss to the Ravens, Gase ripped players he said weren't doing enough studying away from the practice facility. Gase didn't name names, but the Herald said Ajayi was among those being criticized.

"We've got to find guys that will actually put forth effort to actually remember this stuff, and really, it starts with our best players," Gase said.

This would seem to be pretty much exactly the sort of thing Pederson was wary of risking. But Roseman was ready for those questions. The Eagles and the Dolphins do a lot of business (Kiko Alonso, Byron Maxwell, three days of joint practices before this year's preseason game) and basically, Roseman feels he and Miami executive vice president Mike Tannenbaum don't try to stiff one another.

"We do a lot of research on players before we trade for them. Not only did we do a lot of research on a guy like this [leading up to the 2015 draft, in which Ajayi went in the fifth round], but we do that here before we make a deal. Really, in this league, you do business with people that you trust, and we feel like we have a good understanding of what was going on there," Roseman said.

"We also have a good understanding of what we have in our locker room, and the chemistry that we have on this team. We weren't going to bring anyone here that would disrupt team chemistry. We feel very confident and comfortable about the player."

Roseman also indicated that the Eagles' medical staff was satisfied that Ajayi's battered knees, which also caused concern in Miami, won't be a big problem, over the next few seasons, anyway.

The Eagles can certainly use what Roseman characterized as "a physical, downhill running back who can pick up yards after contact, he can make people miss, he had 52 catches his junior year at Boise [State] … when you watch him, if there's an alley, he's getting something, and he's going to impose his will on defenders."

But with seasoned, savvy running back Darren Sproles and dominant left tackle Jason Peters both out for the season, blocking help sure seemed a more pressing need. Roseman said there was no "tree that you just pick tackles off of" —  that you look at what's available on deadline day, and out of that, you calculate what can help you the most.

"I don't think we felt compelled to do anything here," Roseman said. "We thought this was a good opportunity to improve our football team not only this year but going forward."

Tuesday is when Eagles coordinators talk to reporters, but offensive coordinator Frank Reich was reluctant to detail what Ajayi brings or how the team might employ Ajayi, since Pederson hasn't weighed in yet. He did say he didn't think locker-room chemistry would suffer.

"It starts with the players, and the quality of players we have in that room," Reich said. "Starting with LeGarrette, the veteran, and how he responds to something like this. That goes a long way to how the room goes. But then the other key is the position coach [Duce Staley],  and how Duce handles it. And Duce is the best, and Duce commands respect in that room. He will do that with any player that walks in the door."

Asked how all the running back pieces fit together now, Reich said: "We'll have to see how it all plays out. … We're happy with all the guys that we've got in the building. This business is a very competitive business."

How can you keep five running backs happy (not including rookie Donnel Pumphrey, who is on injured reserve)?

"Keep winning," Reich said. "Winning has a way of keeping everybody happy."

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