Honestly, I think this game is a push and whoever can dictate the offense will end up winning it. That being said, as someone who has watched a lot of Cyclone games, here's some thoughts for you (sorry in advance for the long post):
1 - As much as it is being talked about on TV, I highly doubt you'll see a Kane/Napier match up on the defensive end. Kane is much bigger, which causes problems for both. Napier could drive on him until he racks up the fouls or Kane could over power and do the same. Neither coach wants their top guy out of the game due to touch fouls. Instead I think you'll see ISU try and contain, or at least irritate, Napier with Morris/Long. Morris is relatively the same size, a little taller and a little smaller, but Long is 6-4 and isn't a bad defender. It would shock me if you didn't see those two guys try and force Napier into long shots and assists, containing the driving that would get draw fouls. Against Baylor they played a diamond and one, assigning Long to shadow Heslip constantly, allowing the zone to do the rest. Granted Heslip is just a cannon, but it took him out of the game and Baylor, who is bigger than UConn struggled to convert and rebound. I'd imagine they'd do something similar or even double team Napier to slow him down a bit. Or, they could go the other way like they did with Marcus Smart. Just let Napier get his 25 points and clamp down on everyone else. Smart is more like Kane than Napier though, but ISU will try and either limit Napier or his options, finding mismatches somewhere else.
2 - It is not great, by any stretch of the imagination, but don't underestimate ISU's defense either. It has really increased significantly since the WVU loss, where they didn't play any D. Even with those midseason lapses, if you look at points per game, UConn is around 71/63, where ISU is 83/74. ISU is allergic to working the clock. Every missed shot will be run on and any open shot is taken, regardless of timing. ISU averages 74 plays per game and had 80 PosPG vs UNC, however only averaging 66 PosPG over the past three (see Baylor's D that crushed Creighton and is averaging 60 PosPG over the last three, 66 over all). They will run until they collapse. This gives them an average of about 1.12 pts per possession and they give up 1 pts per possession. UConn averages only six less possessions at 68.4 PosPG, but has been averaging up to 70-71 over the past three. That gives them a 1.03 points per possession and 0.92 points per possession allowed. Basically its the exact same spread, just a different speed. While ISU is not a shut down D team, their higher points per game is more indicative of loving to run, than being unable to guard. And the more possessions UConn allows, the better the odds get for ISU. They've only had one game all year where they scored less than 70 against a pretty tough schedule. They're holding teams to 41% shooting, compared to UConn's 39%. If UConn can hold them to 39% by taking bad shots possessions won't matter.
3 - They are not deep. This is the biggest issue with this team made exponentially worse by losing Niang. Edozie/Gibson will be used sparingly to clog up the paint so you'll pretty much see Ejim, Houge, Kane, Morris, then a combo of Long/Thomas (both 6-4 shooters) to fill in the gaps. Someone mentioned earlier they are a second half team, that's because they play timidly in the first to avoid fouls and aggressively in the second with them to burn. They've found ways to out rebound much larger front lines (they had a +10 rebound advantage against Baylor and only a -1 against UNC who out rebounded Providence by 20), but if you get them into foul trouble it shuts down the entire works. They were starting to dominate UNC, then Kane drew his third and he had to play less aggressively after. Almost immediately UNC went on a big run and swapped it from being down to being up eight. If UConn goes for jumpers they play into ISU's hands because they are an aggressive rebounding team for their size. If UConn slashes successfully, especially with taller forwards, they could take them out of their game. ISU may be able to survive losing Kane, since they have another 6-4 shooter off the bench, but losing Houge or Ejim could be a death knell with Niang already out. Daniels, Giffy, and Kromah will need to assert themselves. I'm not sure about Brimah. ISU shut Austin from Baylor down in the paint, making him shoot outside jumpers, which he's pretty good at. So I don't think just being tall is going to be that useful. Someone like Embiid, who is tall and aggressive on the glass, gives them fits. Other forwards who had their way with Iowa State are Nash from OSU, Wiggens from Kansas, and Cory Jefferson from Baylor; all 6-9 slashers who can shoot a consistent 10 footer.
4 - Their style of play is slash and shoot. They lead the nation in assists per game. (Kane averages 7 per game and Morris averaged a freakish 6.5 assist to turnover ratio in B12 play) Everyone on the team looks for the open guy and they space very well. If the defense collapses on the drive, the open shooter will take it. All of the top seven will shoot the open three and Ejim will hover around the three point line like Kane to drive or shoot depending on the D. If the defense doesn't collapse they're going to the bucket (See the play for the end of the UNC game). They average 47% over all (53% in the last three) and their second half percentages the last few games are just sick due to fast breaks. ISU follows a philosophy of wanting to make more free throws than their opponents take. Against UNC they made 15 FTs to UNC taking 15. Against Baylor in the B12 champ game, ISU made 18 and Baylor attempted 16. Baylor is much bigger than UConn. They don't have a lot of fear around the basket and play a bit bigger than their height due to solid positioning, kinda Barkleyesque. They are second in the nation in defensive rebounding, which feeds their fast break. They are averaging 87.4 points per game in the post season against 5 NCAA tourney teams.
5 - If basketball is a game of streaks, the Cyclones are the kings. They've garnered the nickname of the Cardiac Clones because they will go on dramatic streaks in both directions. They started 1-17 against Baylor and missed the first seven against UNC I believe. This inconsistency is quiet consistent. The only game with a rated opponent where I saw them put it together from beginning to end was Kansas. They will offer UConn plenty of opportunities to go on big runs with droughts on quick baskets. It is the downside to their style. If they are hitting they are deadly, if they are missing they're giving free opportunities. The other side of that is they've earned their "clutch" description, its not a one off. They play their best in the last 5-10 minutes of games and have shown the stones to shoot lights out when it matters most. They've come back from 10 point deficits something like 10 times this year, including an 18 point one earlier in the year. However, I believe they are undefeated if leading at half. They are battle tested too. The four #1 seeds in the tourney have a combined 8-5 record against the AP Top 25 heading into the tourney (according to Yahoo Sports). To put that in perspective, ISU had an 8-2 record against the Top 25 prior to last Friday. They won't get rattled easily, outside being in foul trouble.
All in all this should be a fantastic game with two NBA minds tossing out plays. I imagine we'll see mismatches galore on both sides. I think UConn could have the D to slow down Iowa States offense and speedy guards to give them fits on the drive. If the Huskies are held to jump shots though Iowa State should have the advantage with UConn's lower shooting percentage and ISU's rebounding edge keeping UConn from setting up their D. These teams match up extremely well together, it should come down to the last few plays and be really fun from beginning to end.
) I took a quick look on ESPN regarding season stats to see where both teams ranked (injuries aside) and was honestly surprised at what I found: