The West Bromwich Albion striker made no secret of his desire to leave the Hawthorns once the Baggies relegation from the Premier League was confirmed last season.
Rondon underwent a medical on Tyneside and begins a season-long loan deal with Dwight Gayle moving in the opposite direction. Newcastle will pay a £2m fee.
The Venezuelan striker scored 10 goals last season as West Brom’s last-ditch revival couldn’t stop them dropping into the Championship.
Newcastle were the second-lowest scorers outside of the bottom six. Rafa Benitez knew that he had to address the problem, or the Magpies faced a relegation battle.
Rondon joined West Brom in 2015 from Zenit St. Petersburg where he scored 28 goals in 58 games. Since moving to the West Midlands, he netted the same number in 119 games.
Completing the deal is Dwight Gayle’s move to West Brom. The former Crystal Palace striker is an experienced lower league player, scoring 23 in Newcastle’s Championship winning season, and 13 for Peterborough in their 2012-13 Championship season.
It’s experience West Brom badly need. Saturday’s 2 – 1 home defeat to Bolton saw them slip in the odds for the title; if Darren Moore is to be a success, he needs Gayle to rediscover he predatory instincts quickly.