Ospreys came out strong and put Quins under pressure early on but it was Quins who put the first points on the board when the Welsh side were caught offside and Adrian Jarvis (who had taken Chris Malone's spot at fly half) kicked 3 points.
Ospreys evened the score when Mike Brown was penalised for not rolling away from the tackle and Henson started his points tally with a penalty kick from just inside the halfway line after 22 minutes.
After 27 minutes, Ospreys took the lead for the first time in the match when Quins were penalised for coming in from the side, and after advantage was played Henson's kick was again successful.
The first of three Osprey players sinned by referee Huw Watkins followed. The first was after 29 minutes, when Paul James pulled down a line out maul, followed by full back Lee Bryne who spear tackled his opposite number Mike Brown after the Quins player had received a high ball from Adrian Jarvis. The third card was shown to Henson when he did an illegal shoulder charge on David Strettle.
Quins failed to capitalize on the 3 man advantage and it wasn't until 7 minutes into the second half with only Henson left in the sin bin did Quins use the advantage. The points came from De Wet Barry when he followed up a through kick from Jarvis.
Towards the end of the first half Quins were denied the first of their two controversial disallowed tries when the referee was not convinced the ball had been grounded after the ball was driven over the line. The long wait from the video ref left the crowd a little annoyed.
The second, and maybe a little more controversial, was right in front of the referee. Sonny Parker was fortunate not to be sent walking to join his team mates in the sin bin when he pulled back Chris Robshaw as he chased a chip through from Jarvis. Again the video ref was called into the game and a no try was given, much to the confusion of the crowd.
With 5 minutes remaining on the clock, the fourth official was again called, this time to give an answer to whether De Wet Barry or Robshaw had got their fingertips to the ball as it crossed the try line.
Quins had benefited from an earlier possible try that was given when Ospreys had failed to ground the ball after their forwards drove over Marty Holah..
Three minutes after De Wet Barry's try, Henson returned to the pitch and made up for the earlier yellow card with a superbly kicked penalty to put the Welsh team ahead again. 8-9
Ospreys stretched their lead when Henson again added another penalty and a well timed interception which saw him score the first Osprey try. He finished the scoring by converting his try.
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