Gary Cahill is due to undergo a medical at Chelsea with a view to completing his move from Bolton over the weekend, Press Association Sport understands.
The England defender was in London overnight and looks set to end two weeks of uncertainty over his future by joining the Blues.
It is more than a fortnight since Bolton accepted a £7million bid from Chelsea for their prize asset, whose contract expires at the end of the season.
Negotiations initially looked to have hit a snag when Chelsea boss Andre Villas-Boas revealed club and player were "miles apart" in terms of Cahill's salary.
Reports suggested Cahill was looking for £100,000 a week, with Chelsea hoping to settle for something closer to £70,000.
The club are looking to reduce their overall wage bill due to the Financial Fair Play regulations but the two parties now appear to have come to a satisfactory conclusion.
Speaking on Friday, Villas-Boas appeared confident of a positive outcome "this week" and refused to criticise Cahill or his representatives for the delay.
"It's part of negotiation," Villas-Boas said. "I'm sure all parties are protecting their interests and we'll reach an agreement."
Cahill, 26, would be Villas-Boas' first January signing, bolstering the problematic central defensive area.
QPR target Alex is out of favour and has not been considered for first-team action since being made available for transfer and Branislav Ivanovic has been injured, while both David Luiz and John Terry have been short of their best this season.