"The title was a big goal of ours at the start of this season," Holley told the Western Mail.
"We talked a lot to the players about the fact that nobody had ever defended the Magners League title and we do take it really seriously.
"The Magners is a fantastic competition now, the Italians have added to it, and you do have to show your strength-in-depth and you do have to go to places and get results.
"We seriously want to defend it. We want to make the top four but if we get something in Edinburgh, we may look at that again. We aren't taking anything for granted."
"Now we are in a very strong position. We are really satisfied with the culture at the Ospreys and the young players coming through.
"They are now gaining in belief and confidence and we are in a good place."
With just five rounds of action remaining until the play-off stages commence, the Ospreys have crucial home ties against two of the three teams around them in the table with Munster and the Blues still to travel to the Liberty Stadium.