World number 148 Evans was playing Harris for the first time
Briton Dan Evans surged into the Delray Beach Open quarter-finals in Florida with an emphatic 6-0 6-2 win against South African wildcard Lloyd Harris.
The 28-year-old British number three, a qualifier in this event, won the first nine games and secured a comfortable victory in an hour and eight minutes.
Evans, who beat defending champion Frances Tiafoe in the previous round, faces Italian Andreas Seppi next.
Sixth seed Seppi beat Australian Jordan Thompson 7-5 6-1.
