Newcastle will have to pay for Salomon Rondon next summer after West Brom move
Newcastle United signed the striker on a season-long loan on transfer deadline day last week.
Dwight Gayle joined the Championship club, also on loan, as part of the arrangement.
Rondon had entered the final year of his contract at The Hawthorns, and the 28-year-old – who had had a £16.5million release clause in his deal – would have been available on a free transfer next summer.
However, West Brom are understood to have taken up the option of an additional year, meaning his contract with the club now runs until 2020.
Rondon, handed the No 9 shirt, made his United debut in last weekend's 2-1 defeat to Tottenham Hotspur at St James's Park.
The Venezuela international – who had come off the bench in the club's Premier League opener – struck the crossbar in the second half as Rafa Benitez's side pressed for an equaliser.
Speaking about Rondon, Newcastle manager Benitez said: "We talk about characteristics of a player and Rondon he is strong, he can keep the ball and link with the others, and at the same time he has more mobility.
“He can give us this physicality, and this kind of player that sometimes we were missing when we were under pressure.
“He can hold the ball and move forward. Joselu is doing a good job, but maybe is not as strong as Rondon. He has clever movements, but maybe is not as quick as (Yoshimori) Muto.”
Rondon is pushing for a start against Cardiff City on Saturday.