Match ends, Ross County 4, Aberdeen 1.
Aberdeen suffered a "horrible afternoon" said manager Derek McInnes as they were hammered 4-1 by Ross County in Dingwall.
To make matters worse, Jonny Hayes, Ross McCrorie and Ash Taylor were all injured in the rout.
Ross County rose off the bottom of the Scottish Premiership with their first home league win since the opening day of the season.
"At both ends of the pitch we weren't good enough," said McInnes.
Oli Shaw and Charlie Lakin drove County into an early 2-0 lead before an Alex Iacovitti own goal on the stroke of half-time gave Aberdeen hope.
But as the visitors faltered in front of goal, Shaw scored again before Jermaine Hylton made it four.
"I'm as disappointed by the last 10 minutes as I was by the opening," McInnes told BBC Scotland. "We have two players leaving here on crutches, it's been a horrible afternoon for us."
It is the second win in six games under Hughes since he took charge last month, and moves them up to 10th in the table.
However for Aberdeen, it is now just one win in their past five games as they fall to fourth.
It is a result that will send shockwaves through the north-east. Within seconds of kick-off, they were behind amid a calamity in the Dons defence.
Andrew Considine's pass was loose, and Tommie Hoban fell over in the box while cutting out Lakin's pass to gift away possession. But, despite a flurry of red shirts, no-one could get close to Shaw, who in the confusion drove a shot low into the bottom left-hand corner.
Passes went astray and it got all too scrappy at times, but both sides were getting forward. Aberdeen threatened through Curtis Main and Sam Cosgrove, but just as they began to look more dangerous County stunned them with a second.
Lakin collected the ball in space on the left of the six-yard box and sneaked the ball into the bottom corner.
Every time Hughes' side marched forward they looked like scoring as Aberdeen's defence wobbled, and Regan Charles-Cook's cross was begging for a blue shirt to knock it in, while Lakin had a long shot that just deflected wide.
Yet Aberdeen looked like they too had a goal in them. Home goalkeeper Ross Laidlaw made point-blank saves twice from Scott Wright, Lewis Ferguson had a free-kick deflected over, and Hoban and Cosgrove both had strong penalty shouts.
But they did get a break when Hoban's header deflected off County defender Iacovitti and trundled over the line to pull one back before the break.
The story of Aberdeen's game was summed up in one attacking move. Wright made a great pass to Matty Kennedy on the right, whose ball across goal expertly found Cosgrove. But the striker, once so deadly in that position, let it slip through his legs.
But County were not only repelling what Aberdeen had, they found a second wind going forward. Shaw struck a shot from distance that just whistled the post, but he made no mistake when Ross Draper's header fell to him and he hit it first time past Joe Lewis to seal the three points.
Even then they were not done. The gloss was put on the result when Hylton raced on to a pass, Lewis' attempted clearance bounced off him, and he just had to knock it home to add a fourth.
Man of the match - Oli Shaw
What did we learn?
It is now a second win under Hughes, just one short of their entire haul under Stuart Kettlewell this season. They both have come against Hibernian and Aberdeen - sides in the top four of the Premiership - suggesting perhaps their best stuff is reserved for the better sides in the division.
Aberdeen created plenty of chances, but the once-prolific Cosgrove is struggling to find his old form while Main cut a frustrated figure again.
In defence they simply fell apart, and an unhappy Aberdeen support will be asking questions of the result.
What did they say?
Ross County manager John Hughes: "What they [the players] have given me since I've come in is they give me everything they've got. No matter who we play, win or lose, they'll know they've been in a game. I've got a committed bunch of boys. To get a reward like that, I'm really pleased for them.
"That victory is for the chairman and everyone at the club."
Aberdeen manager Derek McInnes: "The defending wasn't good enough. At both ends of the pitch we weren't good enough. We created numerous chances. At half-time it was about trying to pick up where we left off. But some of the chances we missed were not good enough."
Ross County travel to Ibrox next Saturday to take on league leaders Rangers (15:00), while Aberdeen are at home on the same day against Motherwell (15:00).
- 5MorrisBooked at 49mins
- 17Charles-CookBooked at 59minsSubstituted forDraperat 65'minutes
- 8ShawBooked at 87minsSubstituted forMckayat 88'minutes
- 14TaylorSubstituted forLoganat 31'minutes
- 17HayesSubstituted forNgwenyaat 64'minutes
- 9MainSubstituted forAndersonat 76'minutes
- Bobby Madden
- Shots on Target
Second Half ends, Ross County 4, Aberdeen 1.
Goal! Ross County 4, Aberdeen 1. Jermaine Hylton (Ross County) right footed shot from outside the box to the centre of the goal following a fast break.
Attempt missed. Billy Mckay (Ross County) right footed shot from outside the box is close, but misses the top right corner. Assisted by Jermaine Hylton.
Substitution, Ross County. Billy Mckay replaces Oli Shaw.
Oli Shaw (Ross County) is shown the yellow card.
Offside, Ross County. Iain Vigurs tries a through ball, but Oli Shaw is caught offside.
Goal! Ross County 3, Aberdeen 1. Oli Shaw (Ross County) left footed shot from the centre of the box to the bottom left corner. Assisted by Ross Draper with a headed pass following a corner.
Corner, Ross County. Conceded by Ross McCrorie.
Substitution, Aberdeen. Bruce Anderson replaces Curtis Main.
Attempt missed. Oli Shaw (Ross County) right footed shot from a difficult angle and long range on the right is close, but misses the top right corner. Assisted by Harrison Paton.
Foul by Curtis Main (Aberdeen).
Callum Morris (Ross County) wins a free kick in the defensive half.
Corner, Ross County. Conceded by Kieran Ngwenya.
Offside, Aberdeen. Andrew Considine tries a through ball, but Scott Wright is caught offside.
Hand ball by Iain Vigurs (Ross County).
Foul by Curtis Main (Aberdeen).
Connor Randall (Ross County) wins a free kick in the defensive half.
Joe Lewis (Aberdeen) wins a free kick in the defensive half.
Foul by Jermaine Hylton (Ross County).