49ers' Christian McCaffrey declined to inquire about Frank Gore's No. 21 out of respect
Christian McCaffrey Nominated for Fedex Ground Player of Week 2
49ers news: Christian McCaffrey said he has too much respect to wear Frank Gore's #21 jersey - Niners Nation
Christian McCaffrey Football Shirt Jersey #23 San Francisco (Small, Black) : Clothing, Shoes & Jewelry
Look: 49ers Reveal Christian McCaffrey's New Jersey Number
New 49ers RB Christian McCaffrey 'extremely fired up' to join Kyle Shanahan's offense
Christian McCaffrey serves warning to rest of NFL with San Francisco 49ers admission - Mirror Online
Christian McCaffrey gets jersey No. 23 after trade to Niners
Christian McCaffrey Trade Reactions! Are the 49ers contenders?