Terms of the deals were not disclosed.
"This is where I want to be," Neagle said in a news release. "From the start, I knew I needed more games to get better, and now I'm ready to make a difference. The biggest difference is my confidence and feeling comfortable on the field, and confidence comes from playing games and playing well."
In 2010, the Tacoma native scored 12 goals in 19 games for the Charleston Battery of the USL-2. He was the USL-2 MVP and Golden Boot winner and the Battery won the league championship.
He then played for IFK Mariehamn of Finland, scoring two goals in five games.
"We welcome back Lamar," head coach Sigi Schmid said in a news release. "The year away was very beneficial to him. He's a versatile player who can play up front as well as wide midfield."