Iraola says he's been following Delap's progress this season.
He said, "I think he's a player that is very complete because obviously he's a tall player, they can use him in their direct play. He's very good linking up play but he’s also quite dynamic and he attacks very well the spaces, asks for the balls in behind, very good also creating fouls, set play situations for them.
"In the Premier League it's always like this. You come from a very difficult forward, you go to another one.
"They have also different kind of players behind him, Hutchinson, Szmodics also that are big goal threats, very good full backs, putting crosses from outside.
"It's going to be tight because all the games that they are playing are being very, very tight. I hope mentally, physically we can start the game at our 100 per cent because I think we will need it because it's the probably the most difficult one in the way that we had a good amount of days between Wolves and Spurs, but this one is a difficult one."
On Ipswich overall, Iraola also said: "I think they've been very competitive in every game and this is the most difficult thing in the Premier League.
"You know, they haven't gone anywhere and they've lost very, very easy. No, no, I think the games they haven't won or they've lost, they have been by very small margins.
"And this means that they have obviously after the time with the manager, with a lot of the same players, a clear idea, clear identity, different options depending on the players they choose. Also like us, they can move a little bit, the players, especially the ones behind Delap and tactically be a different team.
"And it looks, I haven't played against them, they have a spirit.
"This type of teams that they continue and the next one and the next one. And I think it's going to be a difficult challenge for us."
- Get breaking football news faster with the new Tribal Football app! Download now on iOS and Android to stay ahead of all the latest transfers and football updates. Download now: App Store, Google Play