The Bhoys host Derek McInnes' men in a top-of-the-table Scottish Premiership fixture at the weekend, with Aberdeen currently three points behind Celtic in second place.
Deila's side also have a game in hand, however, and the Norwegian feels a win for the Hoops will put them in the strongest of positions in the title race.
RD on Sunday's game against @AberdeenFC : "It is the most important game we have this season. If we win it’ll be very hard to reach us."— Celtic Football Club (@celticfc) February 27, 2015
RD: "Aberdeen has to win, maybe a draw, to stay in the fight for the championship. If we win then we’re in a very good position."— Celtic Football Club (@celticfc) February 27, 2015
Deila knows neutrals will prefer a closer fight, even if Celtic were to prevail, but says he has to put his side's needs above that of the Scottish populace's as a whole.
Indeed, the Norwegian would rather stay 'alone,' comfortable at the top and out of Aberdeen's reach.
RD: "I can see that for the country it’s important to have excitement in the league but I’d rather stay top, alone and comfortable."— Celtic Football Club (@celticfc) February 27, 2015
Meanwhile, reacting to last night's Europa League exit at the hands of Inter Milan, Deila spoke positively of the future, telling reporters he has already seen plenty of progress at Celtic Park.
That progress, the 39-year-old says, is sure to continue - as he is optimistic that he has a young group at Celtic destined for big things.
RD on last night's defeat to @Inter : "I’m proud of the boys. We showed we have really improved but this is just the start." (MD)— Celtic Football Club (@celticfc) February 27, 2015
RD: "I’m a coach that likes to work with development and see progress. The players here are young and I’m optimistic for the future."— Celtic Football Club (@celticfc) February 27, 2015