The Premier League newcomers were beaten 2-1 at home by Bournemouth.
Despite putting in a creditable display and being a 1-1, they conceded in the last minute to throw away a valuable point.
Post-game, Chaplin said: “That's right up there. Tough to take. I don't feel like it was justified.
“Yes, it hurts a lot. The lads are gutted in the changing room. I think this is the game that we felt like we could have won.
“I don't know the time of the first goal but it felt like we were the better side, creating the better chances.
“We defended really well in shape and counter-attacked really well in the second half as well. Yes, it’s tough to take, really tough to take.”
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