Bradley missed 12 games with a right knee sprain. He was in the starting lineup Friday night against the Orioles.
Bradley was batting .286 in four games.
Holt says he started feeling "a little weird" during the team's series in Detroit earlier this month. He says he tried to play anyway, "but it just didn't feel right."
He described the symptoms as "a little dizziness, a little light-headedness."
Holt is batting .133. He has two hits and one RBI in 15 at-bats.
Holt hopes some time off will "help me kind of settle down a little bit."