play second fiddle to someone

7. PHRASE : V inflects, oft PHR to n

If you play second fiddle to someone, your position is less important than theirs in something that you are doing together.

• She hated the thought of playing second fiddle to Rose.

..... Cobuild

• I'm tired of playing second fiddle to John. I'm better trained than he, and I have more experience. I shouldn't always play second fiddle.
• You'll have to choose between your wife and me. I won't play second fiddle to anyone.
• Radio has been playing second fiddle to television for decades now.

Usage notes: sometimes used without play

Etymology: based on the literal meaning of second fiddle (the lower part for a violin, a musical instrument with strings)

..... http://idioms.thefreedictionary.com/play+second+fiddle