Celta coach has told Lopez he is free to leave.
Tottenham have snapped up striker Vincent Janssen.
The Frenchman does not seem to be set on bringing in some countrymen.
The midfielder was used almost exclusively as a substitute in the final weeks of last season.
Joel Ekstrand's injury problems are said to have scuppered his move to Elland Road.
Tommy Elphick, Pierluigi Gollini and Aaron Tshibola have all joined the club this summer.
The former Hammers defender believes Carroll can be a key man for the club this season.
Here is how West Bromwich Albion will line-up for their pre-season friendly against Paris Saint-Germain.
The winger could be set to link up with his former manager Jorge Jesus.
Celtic were beaten by the Gibraltar based minnows in the Champions League on Tuesday.