The Washington Nationals have considered an extension for Bryce Harper, says Mike Rizzo.

However, there have been no formal talks.

Scott Boras says he and the Nationals have held informal discussions about an extension for the 23-year-old.

"My attitude is that you certainly want to know what they have to say," Boras says. "Then, you talk about what they want to do. Historically, these type of players, it's very difficult because often there are not player comparables that drive this contract."

Harper is three years from free agency. He'll be just 26.