Oakland will need to make a corresponding 40-man move to create room for Jackson, as its roster is already at capacity. The club may elect to shift injured righty Andrew Triggs from the 10-day disabled list to the 60-day DL, thus opening up a spot for Jackson, per Slusser.
The promotion of Jackson is rather notable because it puts him in position to tie a major league record. The A’s will be Jackson’s 13th MLB team, matching former reliever Octavio Dotel’s all-time mark. Jackson joined the A’s on a minor league deal on June 6 and earned his way back to the majors with a 4.02 ERA and 16 strikeouts against eight walks over 15 2/3 innings/three starts with their Triple-A club. Overall, including 55 2/3 frames with the Nationals’ Triple-A affiliate, Jackson has logged a 3.53 ERA with 7.9 K/9 and 3.8 BB/9 this season.
Now that he’s heading to the A’s, who have several starting options on the DL, Jackson will be in position to earn at a $1.5MM rate. The 34-year-old will also bring significant experience to the team’s rotation, having amassed 377 appearances and 288 starts since debuting with the Dodgers in 2003. Jackson has registered a 4.67 ERA with 6.94 K/9, 3.55 BB/9 and a 43.7 percent groundball rate over 1,800 1/3 MLB innings. He racked up 76 of those frames in Washington last year, when he struggled to a 5.21 ERA despite playable strikeout and walk rates (7.11 K/9, 3.43 BB/9). Jackson also averaged 93.5 mph on his fastball and recorded a 10.1 percent swinging-strike rate, as MLBTR’s Steve Adams noted last month.