Last weekend's 20-9 reversal to Northampton Saints ended any chance the GUINNESS PRO12 table-toppers had of progressing out of their European pool.
But Steve Tandy's men must take on GUINNESS PRO12 rivals Benetton Treviso on Saturday, and Dirksen is adamant that there is more than just pride at stake.
"The pressure isn't off because we are out of Europe," the 23-year-old told the South Wales Evening Post. "Every game is important. We want to win to give us momentum going back to the GUINNESS PRO12.
"Treviso have had a tough season we expect them to come out firing against us. We've lost out there before, so we know it won't be easy.
"We have to go there and be positive. We are out of Europe, but we can't be negative.
"We have had a couple of disappointing games in Europe which we could have won, but the positive is we are competing and hopefully next year we can grow as a team and turn the tight matches into wins.
"Our mistakes are costing us the games, so the main focus this week is on taking opportunities. If we can pull back on the mistakes in Europe next season we will be a good team."
Ospreys recorded a comfortable 44-13 victory over the Italians in round 1 of the GUINNESS PRO12 at the Liberty Stadium, before winning there again 42-7 in Europe.
But the Italians are an entirely different prospect at the Stadio Monigo, and have found some form of late to move off the bottom of the league.
Dirksen will line up in the centres on Saturday, and will team up there with former schoolmate Josh Matavesi, the pair a part of 2009's all-conquering Truro College team.
He added: "It's nice to get some game-time in the centre. The last time I played there was in the LV= Cup in November, so I am looking forward to it.
"Josh and I couldn't have imagined that we would both be at the Ospreys playing together. It is funny how it works out, ending up in Wales having started out in Cornwall.
"Playing alongside Josh in the centre will be fun after our college days. He has been great at the Ospreys, adding a lot to the team especially given the injuries we have had in the centre."
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