For the Razorbacks (22-11), Alandise Harris added 13 points, Rashad Madden and Michael Qualls each scored 11, Bobby Portis posted a double-double with 10 points and 13 rebounds and Coty Clarke also chipped in 10 points. Arkansas now moves on to the second round to play either California or Utah Valley.
Manny Arop paced the Sycamores (23-11) with 12 points, Jake Odum finished with 11 points and six assists, Dawon Cummings added 11 points and eight rebounds and Khristian Smith chipped in with 10 points off the bench.
Arkansas shot only 35.3 percent from the field to start the game, but hit on 4-of-11 from 3-point range and scored eight of the final 10 points of the first half to take a 37-31 lead at the break. ISU struggled from the field as well, making only 35.1 percent of its shots in the opening stanza.
The Razorbacks connected on 64.5 percent of their field goal tries in the second half, including 4-of-6 from beyond the arc. ISU continued to have difficulty putting the ball in the basket after intermission, as the Sycamores shot just 35.5 percent from the field in the final 20 minutes, though they did drain 4-of-11 from 3-point range.
Arkansas opened the second half on a 17-5 run to take control of the contest. ISU never got closer than eight points down the rest of the way, as the Razorbacks cruised to victory.
The Razorbacks dominated the glass, outrebounding the Sycamores 46-32. Arkansas finished the night with 6-0 advantage in blocked shots.