The Washington Nationals will be wearing the powder blue jerseys of the Montreal Expos on July 6 against the Kansas City Royals at Nationals Park, Scott Allen of Washington Post reports.

This will be the first time the Nationals will be wearing Expos throwbacks since moving to Washington in 2005.

July 6 will be a flash from the past to the year 1969 when the Expos had their inaugural season 50 years ago. Not only will the Nationals be wearing throwback jerseys, but the Royals will be wearing their original road gray uniforms from their inaugural 1969 season.

The ballpark will also be in throwback mode, as the Billboard No.1 hit of 1969 "Sugar, Sugar" by The Archies will be featured. The scoreboard will have a vintage twist, as the Expos' 'M' will replace the Nationals' 'W'.

Specialty food items will be available to reflect Montreal's Jarry Park in 1969. Montreal's renowned poutine and smoked meat sandwiches will be available at Nationals Park. Expos royalty will also be in the house, as hall of fame outfielder Vladimir Guerrero will be in attendance. 

Although Guerrero still holds the highest batting average in franchise history (.323), Nationals first baseman Ryan Zimmerman now leads the franchise in hits, doubles, RBIs, and home runs. 

Since moving the franchise to Washington in 2005, the Nationals possess a record 1136-1149 (.497 win percentage). The Expos still hold the deepest playoff run in franchise history, as they made it to the NLCS in 1981. The Nationals have lost in the NLDS four times, most recently in 2017 to the Chicago Cubs.