fielder
Baseball term for any defensive player, including infielders and outfielders. Contrasts with 投手 (pitcher).
He played an active role as a fielder in high school.
Check the fielders' defensive positions.
He played actively as a fielder and contributed to the team's victory.
The manager put the rookie in as a fielder.
投手 is the pitcher, while 野手 refers to any defensive player other than the pitcher (and catcher, depending on context).
counter for people
Compound of 野 (field) and 手 (player), literally 'field player'. A straightforward baseball term.