Lyles (forearm) will be activated prior to Sunday's contest against the Diamondbacks, MLB.com's AJ Cassavell reports.
Lyles was roughed up in his second rehab start Tuesday, but Luis Perdomo's (shoulder) injury accelerated the Padres' need for another arm. The club didn't provide the exact role Lyles will serve upon activation, but there is a good chance he claims the vacated fifth starter spot in the rotation. The 27-year-old posted a 4.46 ERA (4.79 ERA as a starter) and 3.1 K/BB ratio as a swingman prior to his injury, so he wouldn't be more than a streaming option in deeper formats if he is deployed as a starter.