Packed with group of players speaking in German (7)
I believe the answer is:
Here is my best explanation:
'packed' is the definition.
'group of players speaking in german' is the subsidiary indication.
'group of players' becomes 'team' (I've seen this before).
'speaking' shows a homophone (sound like).
'german' becomes 'g' (abbreviation).
'team' sounds like 'teem'.
'with' is the link.
(Other definitions for teeming that I've seen before include "Full of, abounding in", "Abundant", "Swarming in to meeting", "Full of people", "Abounding", "Chock-a-block", "Pouring - abounding", "full of creatures?", "Alive" and "(Of rain) falling heavily".)