Brereton Diaz made 39 appearances in all competitions for Blackburn during the 2021/22 season, scoring 22 goals and laying on three assists.
A Chile international born to an English father, the forward is versatile, capable of playing on the left flank as well as leading the line.
Brereton Diaz has now entered the final year of his contract with Blackburn, who exercised the option of extending it by a further year this summer.
The 23-year-old is West Ham’s preferred signing over Burnley’s winger McNeil, despite him having a lot more experience in the Premier League.
McNeil was unable to help prevent the Clarets’ drop into the Championship after they finished the last Premier League season in 18th place, their fate sealed by a loss at home to Newcastle United on the final matchday.
Blackburn finished last season in the Championship in eighth place, six points behind Luton Town who took the last playoff spot.
Brereton Diaz was interesting Leeds United at one point, with La Liga side Sevilla also in the mix for the Chilean.