one-trick pony

British  

noun

1. informal a person or thing considered as being limited to only one single talent, capability, quality, etc

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Example Sentences

They played out from the back through Christian Norgaard and although they could mix it up, they were not a one-trick pony.

From BBC

"You don't want to be a one-trick pony, certainly if you want to be successful."

From BBC

“He’s not just a one-trick pony, down-the-field guy — he’s really impressed me,” Roman said.

From Los Angeles Times

Farrell had what he called his “crutch” — the physical transmogrification — which also sparked a germ of fear in him, of “being a one-trick pony,” he said.

From Los Angeles Times

But such a blindside can be executed only once, and so what had been emotionally affecting about “The Sixth Sense” swiftly became a gimmick — or, in the case of Shyamalan’s much-derided 2004 film “The Village,” validation for those who thought the director was a one-trick pony.

From Los Angeles Times