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Under the sun this season, Hamilton's numbers are dim. He is batting .122 (6-for-49) with no home runs, four RBIs and eight walks. He also has 17 strikeouts and a .429 OPS.
At night, it's a different story. Hamilton is hitting .374 (41-for-109) with six home runs, 28 RBIs, seven walks and a 1.076 OPS. And he only has 14 strikeouts while playing under the lights.
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Hamilton said Wednesday that he has a tougher time seeing the ball because he has blue eyes. An optometrist who talked to ESPNDallas.com on Thursday supports Hamilton's theory and explained why.
"Because of the lack of pigment in lighter color eyes -- like blue or green eyes as opposed to brown -- you get a lot more unwanted light and that can create glare problems," said Dr. Richard L. Ison, O.D., an optometrist since 1990 who currently works in Murphy, just northeast of Dallas.
http://sports.espn.go.com/dallas/mlb/news/story?id=6696741