King allowed six runs on seven hits and one walk while striking out five batters over four innings in a Cactus League start against the Athletics on Friday.
McKenzie has averaged 95.7 mph with his four-seamer this spring, which is up a full two mph from last season, Kevin Acee of the San Diego Union-Tribune reports.
Wagner is dealing with an oblique strain and hasn't done any baseball activity since the beginning of March, Kevin Acee of the San Diego Union-Tribune reports.
Musgrove (elbow) has had his workload eased back after pitching against Team Great Britain on March 4, and it's uncertain if he'll be ramped up in time for Opening Day, per MLB.com.