Mitch Johnson finally got his three-guard experiment on the floor Wednesday night. De'Aaron Fox, Dylan Harper, and Stephon Castle took the court together for the first time in a 123-103 preseason win over the Suns. The Spurs looked sharp running this lineup, and Johnson's willingness to deploy it in a game suggests he's serious about making it work when the season starts. This is the direction the front office has been building toward all offseason, and now we know what it looks like with real minutes against NBA competition. The spacing and pace should give opposing defenses fits if these three can stay healthy and develop chemistry. One preseason game doesn't settle anything, but for a Spurs team that needed to show some offensive punch, this was the debut that matters.