I'd leave him in the 9th spot for the time being. Small sample, but he is doing well in the 9th spot that some managers consider the 2nd leadoff spot. As others have said, his OBP is still lower than Kepler's, although probably splitting hairs at .338 vs .333, but I digress. If Buxton can get his OBP up, maybe you consider moving him up around the All Star Break. I'd just let him thrive in the 9 spot for the time being. Bigger question maybe is where does Sano hit when he returns? 5th or 6th?