The Astros believe Flores, who missed almost two years after a foul ball hit by D-backs outfielder Chris Young hit him on the right shoulder, still has weakness in his throwing shoulder.
If the Astros were to trade for Flores, they would look at him as a project. They would not want to trade a lot to get him.
For the first time since moving to Washington, the Nats have catching depth, which means they could trade Flores.
Ivan Rodriguez will start the season as Washington's Opening Day catcher, while Wilson Ramos is considered the team's backstop of the future. Derek Norris most likely will start the season in the Minors. According to many in the Nationals organization, Norris already has a big league bat, but is making strides behind the plate.
Meanwhile, with manager Jim Riggleman saying that outfielder Laynce Nix has an uphill battle to make the team, the Astros may have interest in the left-handed-hitting outfielder, according to the source. Houston would like to add a left-handed hitter off the bench.
Nix, who signed a Minor League deal with the Nationals last month, is 4-for-13 (.304) with two RBIs in six games.