The Orioles' Single-A affiliate in Delmarva activated right-hander J.D on Monday, Nov. 2.
Hennen, 23, is a native of Waconia, Minnesota. In 2026, Hennen posted a 6.75 ERA with 27 strikeouts and 25 walks over 20 innings in 16 Single-A appearances. He has not yet made his major league debut.
Also on Nov. 2, High-A Frederick activated right-hander Luis Sánchez from the full-season injured list, High-A Frederick activated right-hander Grabiel Salazar from the full-season injured list and High-A Frederick activated right-hander Hayden Nierman from the full-season injured list.
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