Diana Vickers has been concentrating on her stage career
Former X Factor semi-finalist Diana Vickers has entered the UK chart at number one with her debut single Once.
Vickers, who signed a record deal in March, delayed her pop career while she starred in the London stage production of Little Voice.
In the album chart, veteran rock band AC/DC beat Paul Weller to the top spot in a keenly fought battle.
Wednesday's mid-week chart update had shown Weller to be in the lead by just 3,000 sales.
But in the end it was AC/DC's soundtrack to the forthcoming Iron Man 2 movie that triumphed.
The album features 15 classic AC/DC songs selected from 10 of the band's studio albums from 1976 to 2008.
The pole position in the chart gives the band their 10th top 10 and third UK number one album.
Meanwhile the number two place for Weller means the singer has now notched up 12 top 10 albums as a solo artist, adding to the 11 he had while with The Jam and five with Style Council.
Gennaro Castaldo of retailer HMV said earlier in the week: "The thing that's most important is that, while both acts have very dedicated followings, their music is now being picked up and enjoyed by a whole new generation of fans."
UK TOP FIVE SINGLES
1 Once - Diana Vickers
2 OMG - Usher feat. will.i.am
3 Until You Were Gone - Chipmunk
4 She Said - Plan B
5 This Ain't A Love Song - Scouting For Girls
Source: Official Charts Company
Other new entries to the album chart top 10 were Kate Nash's My Best Friend, straight in at number eight, and Meat Loaf's Hang Cool Teddy at number four.
Elsewhere in the singles chart, Chipmunk's new song Until You Were Gone, featuring Esmee Denters, entered the chart at number three.
Tina Turner's The Best went straight in at number nine. The song originally peaked at number five when it was first released in 1989.
Its revival has been supported by a Facebook campaign by fans of Glasgow Rangers football club to celebrate the football club's record-breaking 53rd Scottish Premier League title.