Fulham came out on top of one of the maddest games the Championship has ever seen as Ryan Sessegnon scored a hat-trick on his 50th appearance for the club as they won 5-4.
The home side took the lead very early on when John Fleck was allowed too much time and space in midfield as he charged toward the Fulham goal - his shot was spilled by Button into the path of Clarke who smashed home.
Fulham dragged themselves level, somewhat underservedly, when a terrible back pass was picked up by Ojo who slotted home before Sessegnon got the side ahead just a minute later, smashing home from the left.
United were then level through Clarke again as he skinned Ream and stuck it under Button, but a lightening break saw Ojo deliver a wonderful ball for Sessegnon at the back post to volley in.
Ojo got the side's fourth after some lovely leg work down the right from Kamara set the winger up - the strike took a deflection but the Liverpool loanee didn't care.
Sessegnon got his hat-trick when a lovely ball found him down the left, he took it down and slammed it past Blackman to make it 5-2 to the visitors.
The home side got one back when a deflected strike wrong footed Button, then Clarke got his hat-trick in six minutes of added time as he popped up at the back post to nod home unmarked.
Button 5 : Spilled the early shot for Sheffield United's first goal. Should have done better for the second and will be disappointed to have let the ball under his body.
Fredericks 6 : Linked up well with Ojo down the right when Fulham broke, but his temperament came into question again in the first half.
Sessegnon 9 : Scored a lovely goal down the left to put the side ahead. Got the side's second and continued to cause problems down the left in the second half. His third goal was a lovely take down to beat his man and smash it home. What a performance on his 50th appearance.
Odoi 7 : Was fairly quiet in the first 45 minutes, but understandable with Sessegnon in front of him taking the plaudits. His second half performance was much better and he looked solid down the left.
McDonald 6 : Saw the ball for the goal happening but going to the man left space in behind him. Frustrated the home crowd with his break up play in the middle but it wasn't the best of performances.
Cairney 6 : Didn't have the best of games as Sheffield United closed him down at every opportunity. Lovely defending on the line in the second half saw Fulham keep a two-goal advantage.
Norwood 6 : Tried a few too many show boat passes but started to cause problems as the game became stretched in the first half. Tried the more difficult passes in the second half instead of the easy balls.
Ayite 6 : His movement in the box enabled other players to find themselves free - notably Sessegnon for the third. A lovely double piece of skill in the second half was his best moment of the night.
Ream 7 : Allowed the home side's attacks too much space and time, but did compete well with Clarke as the game went on. Was a different man second half and had a sensational game.
Ojo 8 : Was having a decent game but his positioning was what allowed him to capitalise on a poor back pass and slot home. Despite looking dead on his feet in the second half, he managed to get the second goal.
Kalas 6 : Like Ream, afforded too much space and time to the United attack, resulting in the first goal. Did well in the second half and defended strongly under increased United pressure.
Kamara 7 : Set up the fourth with lovely leg work down the right to play in Ojo. Quietened down after that.
Fonte 6 : Didn't do too much when he was brought on.
Johansen 6 : A few sloppy passes put his side under pressure after coming on at 5-2 - looked too lax on the ball thinking the game was won.