Conversation so far:
What is the Borussia Monchengladbach?
he was part of the team.
Where was the team located?
European.
How long was he on the team for?
Simonsen waited for his contract to expire and moved to FC Barcelona in 1979.
did the team win many matches?
He scored the deciding goal in the 2-1 1979 UEFA Cup Final win against Red Star Belgrade.
What did he do after moving to Barcelona?
In his first two seasons with Borussia Monchengladbach, Simonsen had a hard time, as he only played a combined 17 games and scored two goals.
Why did he play so few games?
He broke into the starting line-up for the 1974-75 season.

Question: How did he get onto the team to begin with?
Self-contained rewrite: How did Allan Simonsen get onto the team Borussia Monchengladbach to begin with?