Dull had six stints with the A's last season, going 0-0 with a 4.26 ERA in 28 relief appearances.
Hendriks started the season with the A's but was sent outright to the minors in July with a 7.36 ERA. He returned in September and was primarily used as the team's "opener." He finished 0-1 with a 4.13 ERA. He also took the loss in the wild-card playoff against the Yankees, allowing two runs in the first inning.