Sunderland confirm key clauses in loan deals

The German youngsters both agreed season-long deals to move to Wearside on deadline day, as Sunderland took their tally of summer signings to nine.

Hoffman arrived from Bayern Munich, while Dajaku signed from Union Berlin having made the switch from Bayern earlier this summer.

On Hoffman, head coach Lee Johnson said: “Thorben is elite on the ball in terms of playing out from the back and he has great pedigree from his learning process and the way that German clubs coach, especially Bayern Munich.

"Like all young goalkeepers he has areas of his game to work on, but he’s agile and an outstanding shot-stopper in close quarters. We are really excited to add another quality goalkeeper to our stable, as we continue to drive competition and quality.”

On Dajaku he added: ”Leon is a really interesting player – he’s a top prospect with good ability, agility and quality – so we are looking forward to adding him to the squad and working with him.

"He’s a hungry player that has shown a strong attitude and desire to come to Sunderland and grow with us, which is exactly what we want.”

Johnson had hinted last week he was eyeing players who could have a long-term future at the club, and so the inclusion of those clauses is a major boost.

“We might determine to use the loans with an obligation [to buy]. I'd always say that generally I'd rather take a loan who I believe could be turned into a permanent at the end of it,” he had said.

“We're on it and we are having active conversations with players and their clubs.

“But I can't guarantee that they will fall, because they are high quality players and that means they are more difficult to do.

“If this is the squad we're going with between now and January, then I think it's been a very, very good window.

“If we get the players in it will be an outstanding one. I know how good the players we are looking at are.

“I'll be honest and say that it won't be easy. It will be a sterling effort if we do get them.”