Sheffield United boss Paul Heckingbottom shrugged off Leeds complaints over a tackle by George Baldock on Tyler Roberts.
Midway through the first half, Baldock flattened Roberts on the edge of the Sheffield United penalty area. The challenge appeared to be two-footed and with both feet off the ground, however play was allowed to go on as the ball broke to Jack Harrison.
After the defeat, Heckingbottom was asked about the incident, to which the Blades boss replied: "Is that the one where he took a knee to his face? I've not seen it but from our point of view almost stopped an attack.
"Tyler's knee seemed to follow through," he said.
The Blades boss also told Leeds-Live he felt it was a fair challenge: "Yeah, from where I was stood."