For many years I have tried to describe the great cricketer Ian Botham ("Beefy" Botham) to other people in my international language school. I try to think of a word to describe someone who always makes his team win even when other people team are not very good. I want this word to describe "Beefy" or maybe Michael Jordan in basketball, or Ronaldo in football. Can you help me please?
Some possible ideas for you:
A go-to player:
She's the team's go-to player [=she is the player that the team relies on] when they need to score late in the game.
You can also simply state that X is a most important player (MIP) or most valuable player (MVP) for the team.
The teams that rely heavily on one man to win a match are called one-man teams:
With Neymar gone, suddenly Brazil’s ‘one-man team’ lacks a man. (source)
You can say that Ian Botham carries his team.
Anchorman: A man who plays the most crucial part or is the most dependable contributor.
"Franchise player", one that the whole organization is built around...
I'd suggest, wunderkind, boy wonder, and whiz kid
: a person of remarkable talent or ability who achieves great success or acclaim at an early age.
[German : Wunder, wonder, prodigy (from Middle High German, from Old High German wuntar) + Kind, child; see kindergarten.]
: a young man whose skills or accomplishments are precocious. [1960–65; perhaps fashioned on German Wunderkind]
: Informal. a youthful and exceptionally intelligent, talented, or successful person. [1940–45]