Nosworthy & Watford denied at the death
Sean Dyche's side had been ahead since a 27th minute strike from another loanee, Michael Kightly.
However, Nosworthy's high challenge on Leeds sub Mika Vayrynen gave referee Eddie Ilderton no choice but to award a penalty which Robert Snodgrass converted.
Watford had earlier missed a penalty of their own.
Also in the Championship, George McCartney and West Ham had a day to forget as the Hammers were humbled 3-0 at Reading.
Things started badly for Sam Alldardyce's side with sub Joey O'Brien sent off. Jack Collison soon added to Allardyce's headache with a straight red.
Meanwhile, the Royals ran in three goals with Simon Chruch bagging a brace.
Up the road in League One, Liam Noble's Carlisle United overcame Scunthorpe United 2-1 at Glandford Park. Noble played the full 90 for the Cumbrians.
At Griffin Park, Brentford, Blair Adams has not featured since November 12th for Uwe Rosler's high-flying Bees.