Bolt (oblique) was transferred from the 10-day injured list to the 60-day injured list Sunday due to a strained left hamstring.
Bolt began a minor-league rehab assignment May 13 as he was working back from an oblique strain, but he suffered the hamstring injury during his third appearance with Triple-A Las Vegas. The 28-year-old is still eligible to return from the injured list in early June, but the new injury is likely to delay his return.