But Tom James' second-half try helped the hosts to a hard-fought 20-16 win at BT Sport Cardiff Arms Park.
It was only their third league home game of the season with a convincing opening-day victory over Zebre followed by a 35-30 defeat to reigning GUINNESS PRO12 champions Glasgow Warriors.
And Wilson was quick to urge his side to build upon their home form.
"Hopefully it's given us a springboard to build some confidence," he said.
"I'm relieved after the last seven minutes of that game, but pleased with a big effort form the players to beat the league leaders.
"It's only our third home game of the season and people forget that and we've had two wins at home and a loss to Glasgow.
"We've talked about building that home record and if we are ever to give ourselves a chance to get where we want to be we have got to be winning at home."
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