Ahead of their return back to Championship football, Sunderland have completed their first piece of summer business in a signing that Black Cats fans will know well.

What's the word?

As per a report from Chronicle Live, Union Berlin loanee will complete a permanent move to Sunderland in the wake of the club's promotion to the Championship.

Sunderland's Sporting Director, Kristjaan Speakman confirmed the news, saying:

"Leon's contract will crystallise [into a permanent move] based on us being promoted. We were really pleased with all of our loans. They've all had an impact on our team and an impact on our success at different times, and that has been really pleasing."

Sunderland fans surely elated

Sunderland's official capture of Germany U20 star Dajaku bodes well for their upcoming fight for Championship survival.

Neil will want familiar faces in and around the dressing room for next season. In some ways, keeping hold of the bulk of the squad, that just achieved a feat that has been four years in the making, will be just as important as adding new faces.

The Black Cats have played it well with Dajaku, allowing him to bed into the side with less pressure and deciding on the deal when they've seen his progress up close and personal.

Despite suffering from illness in the final couple of months of the campaign, the 21-year-old still played a big part in their bid for promotion, featuring 22 times and registering eight returns (four goals, four assists) in what has been a successful spell in League One.

With that in mind, it's evident he has plenty of potential and perhaps with a full season under his belt, he can register even more exciting numbers in the final third.

Dajaku's versatility is one of his best features, and one that Neil will most certainly take advantage of in the level above, with the former Union Berlin man a player who is capable down either wing, having also performed as a wing-back at Sunderland this season, despite arriving as a forward.

It's a promising first signing for the Black Cats, and one that Sunderland fans will surely be happy about.

In other news: Major mistake: Sunderland now set for summer disaster on 36-goal “magician”