on the sidelines

Idioms  

1. Observing rather than taking part, out of the action, as in Bolivia's neighbors remained on the sidelines, waiting to see which faction in the dispute would prevail. This idiom comes from sports. The sidelines are the two lines defining the sides of the court or playing field and the area immediately beyond them where, in such sports as football, the non-playing team members sit. [First half of 1900s]

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Example Sentences

“We were extremely inconsiderate, insular and uncommunicative with each other that things like that always spilled on the sidelines,” the drummer said on the podcast.

From Los Angeles Times

After years on the sidelines, sumo is back centre stage as part of Japan's soft power arsenal overseas.

From Barron's

The “skein of historical fact, local lore, best-guesswork, and poetry” that comprises his book “depended on its subject’s remaining silent and on the sidelines.”

From The Wall Street Journal

Many are from Europe, he told AFP on the sidelines of a tasting, but there is also one from Himalayan springs in Bhutan and another from a mineral water mecca in Mexico.

From Barron's

Or the time when she appeared next to Belichick on the sidelines on game day wearing a reptile mini-skirt and knee-high boots.

From BBC