、。
As expected, they lost the contest.
Literal
Predict-[passive-された]-[fact-ことだ]-[but-が], they [topic-は] contest [in-に] be-defeated-[past-た].
予想されたことだが ('although it was an anticipated thing,') uses the ことだ nominalizer to turn 'was predicted' into a noun phrase, then ends it with the explanatory だ plus the contrastive が. The effect is 'as expected, but...' — acknowledging the foreseeability of a negative outcome. 敗れる ('to be defeated') is more literary than 負ける and common in written reports.