Unless things have changed, the opponent you named will be a human player. The reason for this frustrating result is the recent season reset. At the onset of a new season you may face players whose offensive gear eclipses your defensive gear, or vice-versa.
As we are aware, match-making is based upon trophy counts. Unfortunately, trophy counts are not representative of level/gear/ability during the first few days of each new season. Using my account as an example, factors including the seasonal reset have dropped my trophy count by 750 points. This has resulted in my recent opponents having similar trophy counts but inferior equipment. My barbarian or Ranger can easily one-shot kill this variety of opponent. The result of many of my recent bouts were similar to what you experienced.
I dislike this system but It is what it is and I don’t anticipate any significant changes are forthcoming. The developer seems intent to have the app go down with this ship.