In American college sports, players who do not participate in game action for a year are referred to as "redshirts." Most often, players sit out a year to save a year of eligibility (limited to four seasons). A redshirt year at the end is most often used to earn a second undergraduate degree. A redshirt year can also be placed in the freshman year with the advantage of allowing students to acclimate to their new environment first. As of 2018, a football player is allowed to participate in up to four games in a season without restrictions and without giving up his redshirt.