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

Private-equity dealmaking also slowed down as buyers chose to sit on the sidelines.

From The Wall Street Journal • Jun. 18, 2026

Factoring in Scott McTominay's stomach bug this week, could Clarke leave one of his leading men on the sidelines for the biggest game the nation has seen in almost three decades?

From BBC • Jun. 13, 2026

The root cause was economics: Construction costs exceeded achievable sale prices, creating an appraisal gap that kept builders on the sidelines.

From The Wall Street Journal • Jun. 11, 2026

Argentina coach Lionel Scaloni named an experimental starting line-up against Iceland, with Julian Alvarez, Enzo Fernandez and Alexis Mac Allister joining Messi on the sidelines initially.

From Barron's • Jun. 10, 2026

The audience gasped as I fell, and I glimpsed Martha Karolyi on the sidelines, her face scrunched in a frown.

From "Courage to Soar" by Simone Biles