have in corner
have (someone) in (one's) corner
To have someone who supports, defends, or assists one. It's been great having such a high-profile figure in my corner during this trial. Don't worry, you'll always have me in your corner if you ever need help with this.
have someone in one's corner
Fig. to have someone supporting one's position or goals. (Originally from boxing.) As long as I have Mr. Howe in my corner, I feel confident about what I have to say.