Ethan Ebanks-Landell scored twice as Sheffield United extended their unbeaten Sky Bet League One run to eight games with a comfortable 4-0 victory over Port Vale.
Jack O'Connell went close with a chance for the hosts early on, meeting Mark Duffy's free-kick with a glancing header which went just beyond the far post.
Vale's Sam Foley shot wide from distance and Anthony Grant was blocked in the area.
United went ahead in the 23rd minute when John Fleck's corner was met by on-loan defender Ebanks-Landell who found the net with a firm, far-post header.
The second goal came in the final minute of the half when Ebanks-Landell hammered the ball into the net after the Vale defence failed to clear.
Duffy made it 3-0 with 62 minutes played, pouncing on the rebound to score after Billy Sharp had a shot blocked on the line.
Vale's Alex Jones was denied by a good save from Simon Moore late on before Blades substitute Stefan Scougall rounded off the scoring with a close-range header six minutes from time.