The winner of this year's Mercury Music Prize will be announced at a ceremony in London tonight, with British indie pop quartet Alt-J the bookies favourite at 6/4. However, an interesting market mover has sent tongues wagging as to the possibility of an outsider scooping the £20,000 prize.

When the nominations were first announced SkyBet had Sunderland rockers Field Music at 14/1 for their fifth album Plumb, though today, just hours before the ceremony, the band's odds have more than halved to 6/1. That puts them third favourites behind Alt J and Richard Hawley and Field Music are now shorter than Jessie Ware's record Devotion, which has been quietly tipped for the prize. Early favourite Plan B has drifted out to 9/1, while Django Django have also drifted to 8/1. Reacting to a wave of support on their Twitter page today, Field Music told followers, "Thanks everyone for all the kind wishes. Whatever happens we're going to have a right laugh and maybe even a few shandies." Late market movers can often suggest information has leaked out, so if Field Music's odds go any shorter, we suggest sticking your money on! Odds aggregating website Oddschecker.com has obviously noted the market move, tweeting, "Field Music are the big mover ahead of tonight's Mercury Award, 10/1 tops and cut across the board."

Lauren Laverne and Nick Grimshaw will host coverage of the Mercury Prize, which begins at 9.45pm tonight on 4Music. 

Watch Field Music performing single (I Keep Thinking About) A New Thing during a Guardian Music session, below: