Middlesbrough boss Tony Mowbray has made Frenchman Malaury Martin his first signing of the summer on a one-year deal.
The 22-year-old midfielder made his debut in Sunday's 3-2 friendly victory over Croatian side NK Varazdin after impressing during a trial on Teesside.
Mowbray told the club's official website: "Malaury can do a bit of everything and will be a useful addition to our midfield.
"He can pass, tackle and defend and he has a great shot on him, so we will try to utilise his talents."
Free agent Martin, a former France Under-21 international, spent last season at Blackpool, but injuries did not allow him to make a first-team appearance.