Middlesbrough have signed attacking midfielder Leo Castledine from Chelsea for an undisclosed fee.

Castledine, 20, has signed a four-and-a-half year contract with Boro, having impressed on loan in League One with Huddersfield Town this season, scoring 12 goals in his 27 games for the Terriers.

He had been due to spend the whole season with Huddersfield, but the Teessiders have moved to add him to their squad as they chase promotion from the Championship.

"I'm absolutely over the moon to join what is a massive, massive club," Castledine said, external. "It's a really big step for me in my career and I'm very excited to be here.

"There's always been trust in young players at this club if they can perform, and I want to perform at my highest level."

Castledine joined Chelsea as an Under-15 from AFC Wimbledon and worked his way up to make one substitute appearance for the first team, a Carabao Cup semi-final against Boro in January 2024.

Kim Hellberg will be hoping Castledine's arrival can improve Boro's potency in the final third.

Boro are second in the Championship, six points behind leaders Coventry City but have scored 20 goals fewer than the Sky Blues.

Before their 4-0 win over Southampton on 4 January, they had failed to find the target in four successive matches.