Beyoncé Knowles 'her biggest competition'

Beyoncé Knowles' "perfectionist" sensibility is said to be impacting her music.

The singer has reportedly delayed the release of a new single from her forthcoming album because she is determined to outdo her previous success.

Apparently the star is not worried about other strong female figures in the music industry.

Instead she is concerned that her upcoming record will not match the sales of her previous tunes.

"Beyoncé is a perfectionist – and her biggest competition is herself," a source told British newspaper The Sun.

According to the report, she is looking at her anthem Single Ladies for comparison when considering new material for the charts.

The tune went four times platinum and so she feels there is a lot to live up to.

"She won't put anything out as her first single until she's 100 per cent sure it will be a classic," the insider explained. "She's putting pressure on herself for it to be a hit of Single Ladies calibre, and to make sure she's on top of the game."

One of the tracks that was considered to lead the hits from her next LP was traded in to be featured in a soda commercial.

Additionally another track titled Bow Down was deemed too disrespectful to women and a hypocritical message in terms of listening content for her fans and rivals.

"The first single was supposed to be Grown Woman – but that got cancelled and used as a teaser for her new Pepsi ad," the source added.