I want to highlight a post written on Beyond the Boxscore, SB Nation's saber-slanted blog. According to BtB's writer Satchel Price, J.J. Hardy and Mark Reynolds have been the best SS/3B combo in baseball during the month of June. As he puts it, Reynolds and Hardy have "gone bonkers for the past few weeks." He concludes that Hardy has been the best shortstop this month while Reynolds has been the second best third baseman despite the circus act he calls defense at third.
Check out the entire article, which includes each players numbers before and after June 1st as well as their competition for best left side of the infield: June's Best SS/3B Combo? J.J. Hardy and Mark Reynolds