Rihanna needs to check herself -- and her smartphone -- 'cause she damn well has Matt Barnes' digits ... at least according to Matt's old teammate.
Glen "Big Baby" Davis jumped to Matt's defense today in the dispute over just how much of an item RiRi and MB are, or were ... before Matt told us they were "just past the crush stage."
Davis was on ESPN's "His & Hers" and told Jemele Hill and Michael Smith .... "He REALLY knows her." Now, did he mean that in the biblical sense? Check out the clip.