Manziel told reporters from 92.3 The Fan, the Akron Beacon Journal and Cleveland.com at a charity event in the afternoon that he had not seen the posts and could not comment on them.
Manziel said he spent Thursday and Friday night in Texas before attending the Michigan State-Ohio State game in Columbus on Saturday.
Both posts appeared to have been taken in Austin nightclubs. One showed Manziel holding a bottle while he was singing along to a hip-hop song. The post was taken down later in the afternoon by the DJ in Austin who posted it.
The Browns had their bye week last weekend. They next play Nov. 30 against Baltimore on Monday Night Football.