Saido Berahino is closing in on a deal to join Stoke
After weeks of negotiations they finally settled on an initial fee of £10m plus up to £5m in add-ons based on appearances, goals and caps.
The 23-year-old has been a target for Stoke for the past three transfer windows but he has now completed a move to the bet365 Stadium after holding talks with Mark Hughes.
Earlier in the day when neither Hughes or West Brom boss Tony Pulis sounded too optimistic about reaching an agreement.
Saido Berahino is out of contract in the summer
Hughes said there had been no progress since last week while Pulis described Stoke's initial offer as "nowhere near" Albion's valuation of the player.
However, a breakthrough has now been made and the long-running transfer saga surrounding the former England Under-21 international, which began in August 2015 with a series of rejected offers from Tottenham, could be about to end.
Berahino leaves West Brom under a cloud after failing to make a first-team appearance since September 10, amid claims over his fitness and mental state which even saw him sent to France to train.
His contract at Albion was set to expire in the summer and he refused the offer of a new deal to remain at The Hawthorns. West Brom would have been entitled to compensation for the academy product should he have left on a free transfer to another British club but unsure how much a tribunal would award them they have decided to cash in now.
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Hughes, meanwhile, insists playmaker Bojan Krkic has not expressed a desire to leave Stoke.
The Spaniard has only started six games all season and has been linked with a move to Middlesbrough.
Hughes said: "We saw something in the press saying that if there was an opportunity he'd like to leave. He hasn't said that to me.
"He's our player, he's involved in the squad tomorrow so he's part of what we're doing. I think there have been enquiries but nobody's come back with any bids – we wouldn't encourage them to be perfectly honest.
"If they do come in, maybe then Bojan or his advisor would want to discuss that. But we're not at that point at the moment."