Scorer (noun)

1. A person or thing that scores in a game or competition.
2. A person or thing that marks or records a score or points.
3. A person or thing that compiles or keeps score.

Origin:

From score (verb) + -er.

Examples:

1. He is the leading scorer on the team.
2. The scorer marked down the points for each team.
3. The scorer recorded the results of the game.
4. The scorer kept track of the score throughout the game.
5. The scorer tallied the points for each round.