Middlesbrough open talks to sign Valencia striker

The newly-promoted Teessiders are understood to have opened talks over the 30-year-old former Manchester City frontman as head coach Aitor Karanka looks to boost the firepower at his disposal in the Barclays Premier League.

However, the negotiations are proving painstaking with Boro seeking an initial loan agreement without taking on full responsibility for the player's existing financial package.

Discussions are understood to have been ongoing for some time and, while progress has been made, any deal remains distant.

Madrid-born Negredo scored 23 goals in his one season at City before returning to Spain to join Valencia, initially on loan and then in a £19million permanent switch.

He has managed just five league goals in each of his last two LaLiga campaigns, although his physical presence has proved a major weapon.

Meanwhile, Boro have also been credited with an interest in Negredo's club-mate Antonio Barragan, a 29-year-old right-back.