I'm not sure about 残り一分を切った. I tried gathering some information and found that 残り一分 = 1 minute left. But I haven't seen 切る used in this context before, so I searched the meaning it said "to do (something) in less or within a certain time"
So, I translated it as "When the competition time is less than 1 minute, the result has been set that we lost."
I'm not sure but I think that the situation is that the match isn't actually over yet because there's still less than 1 minute left, but the referee (or someone) assumed that we lost already. Am I correct?
BTW: I'm not an English speaker if you can answer in simple language I would be really grateful. Thank you in advance.