heavy hitter

/HH EH1 V IY0 HH IH1 T ER0/
noun
  1. 1

    A player with a favorable batting average who is especially good at hitting the ball deep into the outfield or farther.

  2. 2

    (by extension) In any sport, a strong, physical player who is particularly effective.

  3. 3

    A person of considerable importance who is a major decision maker or capable achiever; an especially significant organization or an especially functional object.

Source: https://en.wiktionary.org/wiki/heavy%20hitter