The Polish outfit are eyeing up an ambitious move for the Celtic target.
The Czech Republic striker had starred in the Europa League with Lazio and it was hoped he could be a regular goalscorer in English football.
But he broke his leg early on and has struggled to establish himself ever since. This summer Aston Villa moved for strikers in the transfer market this summer. The club brought in Jordan Ayew and Rudy Gestede to supplement the departure of Christian Benteke and Kozak has had to watch on.
He was recently scouted by Celtic ahead of a potential January move for the Czech Republic striker, who has been impressing for Aston Villa's under-21s. Celtic boss Ronny Deila saw him score twice in a recent under-21 tie with Derby County, as reported by the BBC.
With his place in the national team at the upcoming European Championships at threat Kozak is all set to head elsewhere for regular first-team football and it would appear that he is going to make a move away from Villa Park in the near future.
But it would appear that Celtic are not alone in keeping tabs on the player.
The club's manager is Czech himself. Radoslaw Latal was Kozak's manager at SFC Opava before he headed to Lazio in 2008.
He has stated to the site that he is chasing a Czech player who is not currently playing in England, heavily believed to be Kozak.
Piast are currently top of the Ekstraklasa table in Poland, five points clear of Legia Warsaw and he would join countryman Martin Nespor and Kamil Vacek at the club.