Per the Yankees (h/t YES Network), Voit passed the concussion protocol after leaving the game for precautionary reasons:
YES Network @YESNetwork
A scary moment in the bottom of the fourth, but take a deep breath Yankees fans. The Yankees have announced that Luke Voit was removed from today’s game for precautionary reasons and underwent concussion protocol testing. Those test results came back clear. https://t.co/s92l7K6Y7z
Voit returned to New York's lineup on July 13 after missing eight games due to an abdominal strain he suffered in a June 29 matchup against the Boston Red Sox in London.
Since being acquired by the Yankees in a trade with the St. Louis Cardinals last July, Voit has become an integral part of the lineup. The 28-year-old has already set career highs with 85 games, 18 homers and 52 RBI this season. He's also hitting .276/.388/.495 in 319 at-bats.