Bournemouth boss Eddie Howe was left to bemoan Harry Arter's indiscipline after his red card proved costly in a 1-0 defeat at West Ham.
Midfielder Arter received a first-half booking for dissent, and was shown a second yellow in the 77th minute for cynically pulling down Cheikhou Kouyate.
Michail Antonio prompty took advantage as he nodded home a late winner five minutes from time, converting from Gokhan Tore's cross to the back post to seal victory in for the Hammers in the first league game at their new London Stadium.
"I thought it was our game for the taking, but for one lapse of discipline, possibly we would have won it," Howe told Sky Sports.
"We were in total control, our goal wasn't threatened at all and we looked safe.
"The first booking for H [Harry Arter] is the disappointing one, with the second one you are never going to be stopping people going in for tackles, but we have all been told about the new rules on dissent and the referees are clamping down on that.
"We know there are going to be yellow cards, so we have to do better."
"It was a tight game, I thought there was nothing in it, it was a game of few chances," Howe added.
"I felt we were the better team and much-improved second half.
"We were a bit more positive with the ball, we posed them more questions, we had the best opportunities in the game.
"Even with ten men, how we haven't scored at the end, I just don't know. It's disappointing, but we have to brush ourselves down quickly."
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