MIDDLESBROUGH remain confident of wrapping up a deal for Huddersfield midfielder Adam Clayton as the search for a new right-back is stepped up.

Aitor Karanka is keen to have both areas of his squad filled before Saturday’s Championship opener with Birmingham City and Osasuna defender Damia Abella is high in the club’s thinking along with Hajduk Split’s €500,000-rated Avdija Vrsajevic.

A deal for Abella could be an easier one to do, with Vrsajevic understood to be slightly under the number of appearances for Bosnia required to receive a work permit automatically despite a World Cup appearance. He could, though, hold dual nationality and an EU passport.

But Middlesbrough are keen to have a couple of options to work on, knowing Karanka has already been left disappointed this summer by Juanfran’s decision to reject an opportunity to move from Real Betis.

Sources in Spain suggest Abella, a Catalan, was given permission to head for Teesside for talks as Osasuna try to reduce their expenditure following relegation to the Spanish Division Two.

Time is running out for Middlesbrough to fill the right-back slot before Birmingham arrive at the Riverside Stadium this weekend. Kenneth Omeruo is capable of playing that role following his season-long loan move from Chelsea.

The Nigerian, 20, has known he was returning to Teesside for a second spell for a number of weeks but he was given some extra time off because of his appearances at the World Cup with Brazil. Middlesbrough hope to announce that Patrick Bamford will follow Omeruo from Stamford Bridge, although Blues midfielder George Saville is thought to have preferred to stay down south.

Karanka is pleased to have Omeruo back on board. He said: “He is a very important player to us. He’s someone I love to have with us because he’s a player who came here from Chelsea and his mood was perfect. He was always happy and fighting for his position. He was handed the opportunity to play in the World Cup and he is now coming back to us a better player.”

It had looked on Tuesday night as if a deal for Clayton would have been confirmed yesterday, but there was a hitch in negotiations. The 25-year-old is still very much the player Middlesbrough want and he is understood to be quite keen on the switch, so it should still be done.

But Huddersfield’s determination to have a replacement sorted before sanctioning the sale has complicated things, particularly when Middlesbrough’s Jacob Butterfield was the man they wanted.

Butterfield was someone Terriers boss Mark Robins believed could be a direct replacement and represented a good value for money, given that the West Yorkshire club were set to receive a fee of £1.5m rising to £2m for Clayton.

But there is understood to be reluctance on Butterfield’s part to head for Huddersfield and that has slowed things up regarding Clayton. Robins has since had an offer in the region of £375,000 accepted by Liverpool for midfielder Conor Coady.

Middlesbrough released their squad numbers for the new season yesterday, leaving the slots open for arrivals at numbers two and five in the first 11 shirts. Long serving goalkeeper Jason Steele retains his No 1 shirt, despite being regarded as third choice at the start of the season.

Spanish striker Kike will wear nine and other new signings James Husband and Emilio Nsue will pull on 17 and 24 respectively. Omeruo has been given the 22 shirt, while Tomas Mejias has 40.

Boro squad numbers:

1 Jason Steele

3 George Friend

4 Daniel Ayala

6 Ben Gibson

7 Grant Leadbitter

8 Jacob Butterfield

9 Kike

10 Lee Tomlin

11 Emmanuel Ledesma

13 Dimitrios Konstantopoulos

14 Luke Williams

15 Seb Hines

16 Andrew Halliday

17 James Husband

18 Dean Whitehead

19 Mustapha Carayol

20 Adam Reach

22 Kenneth Omeruo

24 Emilio Nsue

25 Rhys Williams

27 Albert Adomah

29 Kei Kamara

33 Richie Smallwood

39 Jonathan Woodgate

40 Tomas Mejias