"our team took the championship" - I was marked incorrectly for this, but this is not only a literal rendering of πήρε, it's also an extremely common way in UK En to say that a team won a championship, cup, competition or whatever.
"Our team won the league." I thing is right as well as "πρωτάθλημα" is "league" in general.
My answer is: our team got the championship. I believe that my expression is exactly the translation of the exercise.
That's a major difference between languages and mathematics, sometimes you can't come to such conclusions.