[Plugin: Redirection] Successful redirect still producing errors

I’ve set up /blog/* to redirect to / and the redirects are successful in the browser. However, although the pages are resolving correctly, I’m still getting 404 notices for the same links.

Is there a way to stop getting the errors?

(I’m comfortable editing .htaccess files, so if that’ll work, please let me know what to include in the .htaccess file.)

Thanks!