** William Hill rises 5.4 pct, its best day sincemid-July, after confirming merger talks with Canada's Amaya
** Co says deal would create a global leader in sportsbetting, poker and casino
** Top riser on Stoxx 600 and most traded byaverage volumes - 1.5x 30-day average in the first hour of tradeon Monday
** Liberum says there will be scepticism to a dealcompleting on a number of fronts but says William Hill clearlynow "in play" as an M&A target
** Deal to merge with 888 and Rank in athree-way combination collapsed in August
** UK peers up 1-2 pct