This is in my opinion a tune up fight for Buatsi who seems like one of the top talents in the sport. Marko Calic was a decent amateur but hasn’t really transitioned to the professional game very well.
Joshua Buatsi is very compact and throws a variety of punches which lead to him getting knockouts because of the variation of his shots. He has a decent defence and good power.
Marko Calic without being mean fights quite stiff. I think when he throws his punches he doesn’t quite get the range right and is easy to counter. I’ve watched fighters who are no where near Buatsi’s level land cleanly on Calic again and again. I don’t think Calic is great at combination punching and doesn’t seem to have that much power.

I think Buatsi will win by knockout in the 6th or 7th round after breaking Calic down and getting the ring rust off.