West Brom have signed Celta Vigo midfielder Okay Yokuslu and Arsenal utility player Ainsley Maitland-Niles on loan for the rest of the season.
Turkey midfielder Yokuslu, 26, has 29 caps, and spent three years with Trabzonspor before moving to Spain.
Maitland-Niles, who has five England caps, is Albion’s fifth signing of the window.
Southampton and Leicester were also in contention to sign the 23-year-old, a product of the Arsenal academy.
Sam Allardyce chances of signing Maitland-Niles appeared to have gone when his interest became public.
However, the Gunners did not want him to join a club who are in contention for a Champions League place – ruling out Leicester – while Southampton felt it was taking too long to reach a deal and withdrew their interest.
That allowed West Brom to move back in and the transfer was finalised before Monday’s 23:00 GMT deadline.
Arsenal boss Mikel Arteta said: “Ainsley is a very talented player and we are proud of his hard work and development with us.
“This decision to go on loan to West Bromwich Albion for the rest of this season is to support Ainsley and his growth further.
“He will be working at a very good club in the Premier League and we all wish him the best of luck during his time at the Hawthorns.”
Speaking about the arrival of Yokuslu, Allardyce said: “It shows that we have been fortunate to get a player of his calibre.
“To get him on loan, with his quality, is really great for the hard work we have done behind the scenes.”
Yokuslu joined La Liga side Celta Vigo in 2018 from Trabzonspor and made 72 appearances, scoring two goals.
West Brom are 19th in the Premier League and nine points adrift of safety.
Andy Lonergan, Robert Snodgrass and Mbaye Diagne also joined the club in the January window.
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