LONDON: Sir Martin Sorrell, wily ceo of WPP Group, has won most of the acquisition poker games he's played over the years – thanks to his ability to read opponents' minds, a well-padded poke, a doctorate in the art of bluff and nerves of steel. 

The latter, this Friday morning, are being tested to breaking point.

On Thursday he made it clear that WPP's £1.14 billion ($2.01bn; €1.45bn) offer on TaylorNelson Sofres' table would not be sweetened, despite the fact that a significant number (7.23%) of TNS stockholders have yet to nail their shares to Sir Martin's mast.

On Monday, WPP claimed it held acceptances for 42.87% of TNS's share capital – well short of the 50.01% needed to seal the deal – and extended the deadline for its offer to 3pm this afternoon (Friday).

On the opposite side of the poker table, certain TNS shareholders are betting that Sir Martin will lose his nerve and up the offer. Sorrell gaze remains steady … or does it?

Data sourced from Wall Street Journal Online; additional content by WARC staff