And after missing out on a home final appearance at the Kingspan Stadium, and becoming the first side ever to win a GUINNESS PRO12 semi-final away from home, Best conceded his side's intensity dropped at the key moment.
"It's bitterly disappointing to have lost that game, a game we thought we dominated and had many opportunities to win it," the hooker told Sky Sports.
"We just took our foot off the pedal a little bit in the second half. We probably tried to play a little bit in our own half.
"They were good, but at the same time we have to be a lot better than that.
"That's the disappointing thing, to have come here and put himself in the perfect position - I think when we look back at that, we didn't play anywhere near our best."
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