ST meaning in Sports ?

In Major League Baseball (MLB), spring training is a series of practices and exhibition games preceding the start of the regular season. Spring training allows new players to try out for roster and position spots, and gives established players practice time prior to competitive play. Spring training has always attracted fan attention, drawing crowds who travel to the warm climates of Arizona and Florida to enjoy the weather and watch their favorite teams play, and spring training usually coincides with spring break for many US students.

Regardless of regular-season league affiliation, teams generally play their exhibition games against other clubs training in the same state. Teams that train in Arizona form the Cactus League and Florida-training clubs form the Grapefruit League.

Spring training typically starts in mid-February and continues until just before Opening Day of the regular season, which falls in the last week of March. In some years, teams not scheduled to play on Opening Day will play spring training games that day. Pitchers and catchers report to spring training first because pitchers benefit from a longer training period. A few days later, position players arrive and team practice begins. Exhibition games usually begin in late February.