FRISCO, Texas -- The Dallas Cowboys had no choice but to keep wide receiver Amari Cooper.

A team can't give up a first-round pick and five years of virtual cost certainty to have a player for 25 regular-season games. Had Cooper walked, what was a win of a trade from the Oakland/Las Vegas Raiders for the Cowboys would have turned into a loss.

Quick aside: with Cooper accepting less to remain rather than taking more money from the Washington Redskins, as sources have said, might the Cowboys revisit that stance with quarterback Dak Prescott? On second thought, never mind.

This is about Cooper.

He transformed the Cowboys' passing game when he arrived in 2018. He was on pace for one of the best seasons by a receiver in team history in 2019. But what stands out most, because it is the most recent, is what he did in the final seven games of the 2019 season.

He caught 26 passes for 341 yards and had one touchdown. He was held without a catch against the New England Patriots on Nov. 24, the first time that had happened since he came to Dallas.

And when the Cowboys' season was on the line on fourth down against the Philadelphia Eagles on Dec. 22, he was on the sideline. It was all just so weird and made no sense. Neither did the explanations from then-coach Jason Garrett. The threat of Cooper, even if he was having a poor game, was more powerful than the threat of Tavon Austin, who was on the field. Put it this way: Would Dallas Mavericks coach Rick Carlisle keep Luka Doncic off the floor for a last-second play to win the game, even if Doncic had a horrific shooting game?

Of course not.

Almost as questionable as the decision to have Cooper on the sideline was the receiver's reaction to stay there. He should have remained on the field whether he was tired or hurting. Dez Bryant would have made sure he was on the field. Same with Michael Irvin and Drew Pearson.

What some folks love about Cooper's anti-diva receiver mindset is countered by those who wonder whether he is a true No. 1 receiver.

With a five-year, $100 million deal that makes him the second-highest paid receiver in the league in terms of average per year, behind Atlanta's Julio Jones, that can no longer be a question. Jones is making $22 million a season. The New Orleans Saints' Michael Thomas, who set an NFL record last season with 149 catches, was the second-highest paid receiver at $19.2 million.

There is no question about their No. 1 receiver abilities.

In 25 games together, Cooper and Prescott have combined for 132 passes for 1,914 yards and 14 touchdowns.

They have mostly been dynamic together. Just think of all the highlights they have had in less than two full seasons.

With more time on task, they should continue to grow together.

But the final seven games of last season can't happen again. And if the Cowboys' season is on the line late in the fourth quarter on fourth down, Cooper can't be on the sideline.

No. 1 receivers have to be game-changers.