Jon Heyman of Fancred outlined several reasons why he won't be dealt before the July 31 non-waiver deadline:
The Nationals (52-53) entered Monday six games behind the Philadelphia Phillies for first place in the National League East. They are also six games out of the second wild-card spot.
Despite the team's struggles to this point of the year, the Nationals clearly still believe they can contend for a playoff spot. While players like Adam Eaton, Ryan Zimmerman and Daniel Murphy missed large stretches of time this season due to injuries, they have returned to the field for a second-half push.
Washington has won the division in four of the last six years but is yet to win a playoff series.
However, it makes sense to at least explore a trade for Harper, especially considering the Baltimore Orioles received five prospects in return for Manny Machado—another pending free agent—earlier this month.
Considering Harper is a six-time All-Star in seven major league seasons and a former NL MVP Award winner, the cost will be significant, even for a two-month rental. However, this could give one of those teams an advantage in re-signing him as a free agent this winter.
With Washington clearly interested in keeping him around next year and beyond, it seems unlikely the squad deals away its best asset.