Kacper Przybyłko says it would be "an honour" to play for Sunderland AFC after going on trial at the Academy of Light.
The striker has been training with the Sunderland squad recently and while no deal is thought to be close, Przybyłko has taken to social media to say it would be an honour to win a contract with the club.
Sunderland need to bolster their attacking options with Jerome Sinclair ruled out for up to six weeks with a hamstring injury.
The transfer window closes at 5pm tonight but EFL clubs can still sign loans and free agents until the end of the month.
The 25-year-old former Poland U21 and Kaiserslautern striker striker is available on a free.
No deal is understood to be close, with the striker having to prove his fitness too at the Academy of Light.
Posting on his Instagram story, Przybyłko wrote: "Hey guys, many thanks for your messages and words! It is currently only a trial but I give everything to sign here!
"It would be an honour to play for such a fantastic and traditional club! Best regards, Kacper."
Przybyłko stands at 6ft 4" has also previously played for FC Koln, and Arminia Bielefeld.
As well as reinforcing the squad, the Black Cats are eager to offload Didier Ndong, Papy Djilobodji and Lee Cattermole, while Bryan Oviedo’s wages mean that offers for his services would be considered.
There remains strong hope at the club that Ndong and Djilobodji, who are yet to return to the club after loan spells elsewhere last season, will be moved on soon.
The Black Cats have fielded a permanent offer for Djilobodji, though a return to Ligue 1 side Djion is not on the cards. Sunderland have held talks over a loan to buy deal for Ndong.
Cattermole’s future is less certain. The midfielder does not appear to be part of Jack Ross’s plans, but his wages make a deal with interested clubs difficult.
Hull City have explored the possibility of a deal, but Sunderland are keen to offload him permanently.