So they worked out former New York Giants backup Ryan Nassib along with three other players Wednesday, including safeties Jeron Johnson and Duke Williams and receiver Lance Lenoir.
The Cowboys have no plans to sign any of the players after the workouts, at least not as of now, per multiple sources.
Cooper Rush and Zac Dysert are quarterbacks on the roster behind Prescott and Moore.
Rush is an undrafted rookie free agent and Dysert was recently claimed off waivers after being cut by the Arizona Cardinals.
The search for another quarterback is not about any unhappiness with Moore, according to a source. He remains the focus as the team's primary backup. They still don't know what they have in Dysert and wanted to take a look at Nassib.
They released undrafted free agent Austin Appleby to make room for Dysert. Having two undrafted rookies in Appleby and Rush appears to be the biggest issue. Neither Dysert nor Nassib have any playing real experience.
Dysert got no action with the Cardinals last season, bouncing between the active roster and the practice squad. He has been with the Chicago Bears, Houston Texans, Buffalo Bills and Miami Dolphins since 2013, but he yet to get in any games.
Nassib was the primary backup with the Giants for the past four seasons, but played in parts of only five games. He missed much of 2016 with an elbow injury.
The Cowboys will likely see what they have in Dysert and now have some working knowledge on Nassib if they need to make another change before training camp.