Arbenit Xhemajli played as a trialist for Sunderland in their pre-season friendly at Gateshead on Saturday.
Sunderland Live revealed at the start of August that Sunderland had been scouting the centre-back this summer as he was due to become a free agent.
Xhemajli, 22, is a Kosovo international centre-back who left Swiss Super League side Xamax earlier this month.
Sunderland became interested as their scouting looks to take a more modern data approach this summer, with non-executive director David Jones highly influential in that change in tactic.
Sunderland are looking to recruit young players that would be classed as untapped potential with potential to have high sell-on value in future, and the 6ft3in defender is seen as exactly that.
The Black Cats' pursuit of the left-footed Xhemajli was seen as highly ambitious given his experience, and last week we were told that the deal was not going to happen, with a combination of new salary caps and Xhemajli's ambitions making it difficult.
But something appears to have changed in the last seven days, and Xhemajli posted a picture of himself arriving at Newcastle Airport earlier in the week.
And while on trial with the club, he was named on the bench for the pre-season friendly at Gateshead - Sunderland's first of the summer - replacing Tom Flanagan as the left-sided centre-back at half-time.
And he showed his aerial prowess in the game, heading against the post in the 55th minute from a Black Cats corner.
Sunderland will now hope to tie the Kosovo international down to a contract in the coming days.
