A pitcher is credited with a game started if he is the first pitcher to throw a pitch for his team in a given game. A starter who pitches a full season in a five-man rotation will generally tally at most 34 games started. There is no minimum innings plateau for a pitcher to earn a game started, but a starter must pitch at least five innings to be eligible for a win.
Beginning in 2018, teams started experimenting with the idea of using an "opener." Much like a closer, the opener is responsible only for an inning (sometimes two). The opener generally gives way to a reliever in the second or third inning. The prevailing wisdom behind an opener is that it's better for a quality reliever to face the top of the order early in a game than a team's fourth-best or fifth-best starting option. It can also be beneficial to have a right-handed opener face an all-right-handed top of the order or a left-handed opener face multiple imposing lefties. Openers are credited with games started and generally have the opportunity to make more starts than a traditional starting pitcher would over the course of a full season.
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