Bayer Leverkusen have kept tabs on Celtic for years, their sporting director Simon Rolfes has admitted.
The Bundesliga club are in town as they take on Ange Postecoglou's Hoops at Parkhead on Thursday night.
In tow will be right-back Jeremie Frimpong, an important player at Die Werkself after his January move to Germany's Rhineland.
Rolfes, in an interview with Sacha Pisani of StatsPerform, explained they were also in for another Celtic star this summer – presumably Kris Ajer, who came close to a move before Brentford swooped in.
And it's clear he sees Scotland and particularly Glasgow's east end as a hotbed of talent.
Rolfes said: "We have watched Celtic in the last years.
"We signed Jeremie Frimpong from Celtic, we were interested in a player from Celtic this summer.
"So we've followed Celtic a lot in the last years, and they had very good international games against AC Milan, for example. I watched that game.
"It's a strong team, you could see that in their first game against Betis. That was a really interesting game."
Leverkusen brushed aside Rangers 3-1 in the final match to be played in Scotland before Covid would banish fans from stadia for over a year.
And Rolfes can't wait to sample another famous European atmosphere in the city.
"The fans are now coming back," he added. "Our last European international game before the lockdown with spectators was against Rangers.
"It was a fantastic atmosphere there, we won that game so for us it's good to come back to Scotland and win again, after the lockdown."
