"He needs to wake up, I think, because they're right in it, they really are," Roberts told the BBC.
"Only Villa in the bottom six have got a worse record in the last 10 games than Swansea. For him to say they're not in a relegation fight - they're four points from the bottom three - they're right in amongst it."
The Swans, who finished eight in the league last season, are in a poor run of form, which has seen them win just one of their last 10 league games and has prompted speculation about Monk's future at the club.
News that makes sense
Your trusted source for staying up-to-date with the world around you. Get free daily news updates and analysis, straight to your inbox.
To add to Monk's woes, Swansea host second-placed Leicester City on Saturday before a trip to leaders Manchester City on 12 December.
(Reporting by Shravanth Vijayakumar in Bengaluru. Editing by Patrick Johnston)
