The Baggies had been confident in landing the 24-year-old this summer until speculated talk of an Arsenal move for his services held things up.
And while the Gunners have not followed up with an offer, that has paved the way for Newcastle to make contact with the French club and West Brom fear missing out on one of their top targets.
Newcastle want to follow up the attacking signings of Siem De Jong and Ayoze Perez by landing at least one new striker before the start of the Premier League season.
And as they struggle to reach an agreement with Lyon for Alexandre Lacazette and Montpellier for Remy Cabella, Newcastle have had to seriously consider alternatives. Riviere represents a much cheaper option from one of France’s richest clubs.
Newcastle will also soon been armed with more money raised from the £12m sale to Arsenal of Mathieu Debuchy, which should be confirmed at the beginning of next week.
A chunk of that will be used to find Debuchy’s replacement, although the Magpies have so far been reluctant to match Feyenoord’s £7m valuation of right-back Daryl Janmaat, who is out of contract next year.
Young Newcastle forward Adam Campbell, meanwhile, is attracting interest from the lower leagues. Swindon Town have tried already to sign him on a season-long loan.