The two teams meet in the first-leg of their Europa League quarterfinal tonight.
Solskjaer told manutd.com: "They've had a very long season but an exceptionally good one as well. They got promoted two years ago, played in La Liga, got seventh and qualified for Europe for the first time and they've played something like 46 or 47 games all season already [in all competitions] – I think only Tottenham have played more competitive games than them this season.
"They've had a great season and we know we'll meet a team with an attitude, desire, experience and a team spirit that is better than many, many teams. We know that when you get promoted and you get those results it is team spirit that will keep you going and their coach has been very impressive and the results they've got so far have been fantastic.
"Of course I watched them against Molde, I don't think I offend anyone when I say I hoped Molde would go through! [Smiles] Granada were too good."