According to NorthAmericanWrestlingRankings.blogspot.com, which started keeping track of wrestlers’ records and ranking them as of Nov. 2006, when Jack Swagger lost to Bo Dallas on the 9/18/15 episode of Superstars it was his 300th televised match as a singles wrestler, making him only the 5th wrestler [behind Randy Orton, Dolph Ziggler, Kofi Kingston, and Sheamus] to have wrestled that many televised singles matches!
Assuming his match vs. Seth Rollins takes place this Sunday at Night Of Champions, John Cena will reach this milestone on that night.
[NOTE: these records count t.v. and ppv singles matches since Nov. 2006 ONLY].