Does OU require a letter of recommendation?
Ohio, or Oklahoma?
When I went to the University of Texas, it was common understanding that folks admitted to Okla Univ had to be in good standing with their probation officer...except for athletes. It might have changed since then.
Seriously, look at the college admittance requirements. Sometimes these are on the web, but not always, however, the admission booklet will say. It is common practice for universities which restrict admission to require recommendation letters, I have written hundreds of them for exstudents. Check with the Univ...on the web, or in the admission handbook.
Even if the university does not require them, it would not be disadvantageous to have one or more in the packet.