online chess doesn't lend itself well to categories like "intermediate"...
for example, I DON'T agree that a 1500-1999 is an intemediate..if we're talking about blitz. in the blitz category, a 1500 player is a rare uncommon player and 1999 is a (very) small fraction of the huge chess.com population.
perhaps, the OP doesn't consider himself a beginner because he's played a good deal of time.
otherwise, #6's advice is spot on and echo what just about everyone has said, insteadly of vaguely implying that perhaps the opponent was cheating- you'd be better served to look over your errors and vow to play better...
this is easier Said then done, btw. and I feel embarrased when I look over my game- so many foolish and onwise decisions.
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my general advice to the OP is to take a sober, humble, and perhaps difficult assessment of your strength. You are well below the chess.com average in every time control. the point of the word "intermediate" is not to feel all good about yourself but to know that you perhaps should start working on your positional chess or learning the fine art of combinations and tricky endgames...
might I suggest that working on these skills when you well below chess.com average is misplaced? of course it doesn't hurt to know some concepts- but perhaps you should obsess on 'Beginner' chess concepts like basic development in the opening, keeping your pawns and peices safe, and knowing the very basic endgames.
the "beginner" word here isn't an insult; its a description that means you cannot advance in chess until you get it...
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this is a suggestion. your attitude is important to chess- if it helps to feel like your NOT a beginner- thats fine. but for me recognizing the weakness of my play, I think, makes me more receptive to learn. I don't discount sage advice from higher players- continue to think about and work on the basics- and just generally keep in the mind that I have ALOT to learn.
I am just an intermediate player, not good at all but no longer a beginner..... I do work on improving my game.... my opponent made 22 excellent moves, .... I'm not even in the same league.
You are very much a beginner or a novice. Terms like 'intermdiate player don't mean much but if you were 1500-1999 you'd be intermediate.
Work on tactics. Seriously if you study nothing else you will improve. Do 8 to 10 tactical problems a day, at least 5 days a week. There isn't much point in studying anything else until you stop hanging tons of material.
Look at your moves with the engine not your opponent's. Asume your opponent will make the best move and you can't change thier play anyway.
It's not that you are not in the same league it's that in that particular game you were putting pieces on squares hoping that your opponent would blunder.
You can't play like that.