In a photo-finish, Adele's 21 narrowly withstands the challenge of Jason Mraz' Love Is A Four Letter Word to keep the U.K. album chart crown. On the singles survey, Carlie Rae Jepsen's "Call Me Maybe" beat off Parlophone/EMI newcomer Conor Maynard's "Can't Say No" for a third week at the summit.

Of all the records 21 has set during its epic run, this week's is the least glorious, since it topped the new chart with sales last week of a mere 17,000, according to the Official Charts Company. That's the lowest total for a No. 1 U.K. album since the Levellers did it with 13,000 for Zeitgeist in 1995. Mraz's opening tally was also 17,000, finishing just 44 copies below Adele's total. Mraz's last album We Sing We Dance We Steal Things peaked at No. 8 in the U.K. in its fourth chart week, in January 2009.

Jason Mraz Vs. Lionel Richie For Next Week's No. 1 Album

Nicki Minaj fell 2-3 with Pink Friday - Roman Reloaded and there were top ten climbs for Lana Del Rey's Born To Die, 6-4, and Ed Sheeran's +, 10-8. Train's California 37 debuted at No. 10 and Spiritualized's Sweet Heart Sweet Light at No. 19. Now That's What I Call Music 81 started a third week atop the compilation chart.

Jepsen's singles supremacy continued with a healthy 114,000 new sales for "Call Me Maybe" - up on last week's 110,000, which in turn bettered the 106,000 with which it entered at No. 1 two weeks ago. 19-year-old Maynard's strong debut at No. 2, on 74,000 sales, follows his victory on MTV's "Brand New For 2012" contest and a sizeable YouTube following. He's currently touring the U.K., with a London date at Dingwalls on Tuesday (24).

"We Are Young" by fun. featuring Janelle Monae climbed 7-3, as John Legend's 2005 hit "Ordinary People" raced 27-4 after being covered by BBC1 talent series "The Voice" contestant Jaz Ellington. The track peaked at No. 27 on first release but now becomes Legend's biggest U.K. single. Jessie J, one of the judges on "The Voice," saw her own "Laserlight" featuring David Guetta, jump 26-5.

Also new in the singles chart's upper echelons were B.O.B.'s "So Good" at No. 7 and "Primadonna" by Marina & the Diamonds, which became Welsh artist Marina Diamandis' highest-charting U.K. track.