As the Dallas Cowboys have emerged as the best team in a lackluster NFC East over the past few weeks, it's no coincidence that their sudden ascent happened almost immediately after they traded a first-round pick to Oakland in exchange for receiver Amari Cooper. Since landing Cooper, the Cowboys are 3-1 and are coming off a huge Thanksgiving win over the Redskins, during which Cooper exploded for 180 yards and two touchdowns.

It turns out, the trade was mutually beneficial for both the team and player. During an interview with Yahoo Sports' Kimberley A. Martin on Tuesday, Cooper opened up about the trade, his time in Oakland, and how he's changed since arriving in Dallas. 

"I feel like it kind of changed me, like, as a person a little bit," Cooper said.

He admitted he wasn't entirely happy with the Raiders, who have since dropped to 2-9 and are now watching the first-round pick they acquired from the Cowboys sink further and further down the draft board as the Cowboys stack up wins.

"I've never been in a situation where I've been traded before. Growing up, every team that I've played on, I was a pretty important piece to the team," Cooper said. "I wasn't really happy in Oakland or anything like that. But when I sat and thought about it [Monday] night … I thought about the fact that they traded me away. I don't know how to feel about it."

He added that he didn't feel like he was being used properly by Jon Gruden's Raiders.

"I looked at it totally different than most people looked at it," Cooper said. "[The Raiders] basically said, 'We could get a guy, who's going to contribute better than he will, in the first round. And I didn't know how to feel about that.

"I just always felt like I wasn't really being used how I felt like I would have used me if I was the coach. So I looked at it from that perspective, not from the perspective that, 'Oh, they don't think I'm good enough' or I'm not good enough.

"I never had those questions in my mind. At all."

As a result, he says he's a changed person and player.

"Just reflecting on my last four games here and my personality here, I feel like it did change me, as far as having that chip on my shoulder," Cooper said. "Not that I wasn't passionate before, but playing with more passion, trying to intentionally have fun out there. It definitely has changed me, in terms of me going out there and just having fun with it. 

"Because when you get traded, you start to think, 'Wow, that can happen.' Just like that."

The Cowboys are a changed team, too. With Cooper in the fold, the Cowboys are scoring 23.5 points per game and averaging 358.5 yards per game. Without him, they scored 20 points per game and averaged 320 yards per game. Cooper has directly contributed 22 catches, 349 yards, and three touchdowns to the cause, but his contributions extend beyond just his stat line. 

Having Cooper on the field forces the Cowboys normally conservative play-callers to open up and modernize the playbook by using more three-receiver sets. Before Cooper arrived, the Cowboys used 11 personnel (one running back, one tight end, three receivers) 60 percent of the time, according to Sharp Football. Since Cooper arrived, they've used 11 personnel 69 percent of the time. 

The mere presence of a WR1 on the field has aided both Dak Prescott and Ezekiel Elliott, the latter of whom is averaging 160.8 yards from scrimmage per game since the Cooper trade. Prescott's passer rating, meanwhile, has risen from 87.4 (without Cooper) to 102.4 (with Cooper). 

Cooper isn't the sole reason why the Cowboys have emerged as the best team in the NFC East. But he has changed the Cowboys for the better. That much is undeniable.