Morse's best moment in a Nationals uniform, he said, was helping the Nationals win their first division title in 2012.
"Whenever you get a chance to go the postseason, it helps a player out in his career," Morse said.
Morse arrived in the visiting locker room around 3:50 p.m. ET on Friday, and he admitted it was weird to be in the opponent's locker room.
"It's weird, and I hope to check it out more often," Morse said. "It feels good to be here. I have a lot of memories. I'm going to focus on winning right now. "
After the game, Morse planned to see his former teammates such as Ian Desmond and Jayson Werth.
"I will just wing it," Morse said on what he plans to do in DC.
Bill Ladson is a reporter for MLB.com and writes an MLBlog, All Nats All the time. He also could be found on Twitter @WashingNats. Daniel Popper is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.