Kentucky (8-1) won its sixth in a row. PJ Washington added 20 points, Shai Gilgeous-Alexander chipped in 15 and Nick Richards had 10.
Monmouth (3-7) has lost three straight. Deion Hammond led the Hawks with 19 and Micah Seaborn had 18.
Diallo, in his first season, helped the Wildcats take a 54-31 halftime lead. Kentucky extended its lead to 29 points in the second half.
