NEW YORK (AP) — The 32 player representatives to the union could vote Tuesday on changes to the NFL’s drug policy that potentially could implement HGH testing.

A person familiar with the talks over the past few weeks told The Associated Press that a conference call vote could come Tuesday evening “depending on the type of proposal” the league presents to the players association.

The person spoke on condition of anonymity because drug policy negotiations between the union and league are confidential.

Both sides have discussed changes to the policy on substance abuse. The union also is pushing for neutral arbitration in the appeals process and is seeking higher thresholds for positive marijuana tests. But the key element could be a test for human growth hormone.