Holmes' contract was selected by the Pirates on Thursday.
Holmes returned to the Pirates on a minor-league deal in December, but he'll break camp with the major-league club after an impressive spring. The right-hander made 10 relief appearances this spring, delivering 9.2 scoreless innings with a 1.03 WHIP and 8:3 K:BB. He made just one relief appearance for the Pirates in 2020, allowing two hits and striking out one over 1.1 innings.