RCA bosses have told the X Factor runner-up that he will be axed if his next single 'Mercy' is not a big hit.
The 24-year-old's self-titled debut album reached number seven on the UK album chart but spent just three weeks in the Top 40. His debut single, a cover of 'Seven Nation Army', reached number nine.
"Marcus's sales have been really disappointing. Although his album went in at number seven, it only spent three weeks in the Top 40," a source told the Daily Star Sunday.
"No-one expected him to flop but he's one of the most unsuccessful runners-up in the show's history.
"He has to pull it out of the bag with his second single. If that bombs, there's unlikely to be a third."
Previous runners-up including JLS, Olly Murs and Rebecca Ferguson have all proved more successful than the winners of their series.
'Mercy' is released on June 3.
> Marcus Collins releases behind-the-scenes look at 'Mercy' video
> TOWIE Maria Fowler: 'Marcus Collins the rudest person I've ever met'
> Marcus Collins: 'Gary Barlow is like my dad'
Watch Marcus Collins discuss his album below: