Newcastle United goalkeeper Karl Darlow

Newcastle have rejected a £5m bid from local rivals Middlesbrough for goalkeeper Karl Darlow, Sky sources understand.

Middlesbrough are preparing a second bid for the 26-year-old with Aston Villa and Reading also thought to be interested.

Darlow started his career with Nottingham Forest before joining Newcastle in 2015.

He made 10 Premier League appearances in the 2015-16 season after Tim Krul and Rob Elliot were injured and became the first choice for manager Rafael Benitez in last season's title-winning Championship campaign.