Louis Riddick breaks down what the Cowboys need out of Amari Cooper, saying that the WR will need to pick up the offense quickly. (1:52)

Riddick: We're going to find out a lot about Cooper (1:52)

Before trading a first-round draft pick for Amari Cooper, the Dallas Cowboys conducted multiple background checks, and all reports came back consistent on the star wide receiver, sources told ESPN.

The people who knew Cooper spoke glowingly about him, according to sources. The list of people the Cowboys questioned for information about Cooper included Nick Saban, his former head coach at Alabama; Cowboys tight ends coach Doug Nussmeier, who coached Cooper at Alabama in 2012 and 2013; former Raiders head coach Jack Del Rio; and Cowboys fullback Jamize Olawale, who played with Cooper for three seasons in Oakland.

Each person recommended trading for Cooper, each vouched for his talents and character, and each person expressed consistent thoughts and feelings, according to sources.

After the Cowboys had done all their work, they felt comfortable meeting the Oakland Raiders' asking price of a first-round pick. Sources tell ESPN that other teams were willing to surrender a second-round pick, but nobody was willing to go to a first-rounder until the Cowboys agreed to the deal last Monday morning.

Dallas is on a bye this week, meaning Cooper is expected to make his Cowboys debut Nov. 5 against the Tennessee Titans on Monday Night Football.