Ross County 2-1 Aberdeen
Teenage forward Steven Ross netted his first senior goal as Ross County defeated Aberdeen in Dingwall.
County moved ahead through Mark Reynolds' headed own goal but the Dons could have been level by the break with Gavin Rae and Scott Vernon going close.
Ross finished well with a shot across the bows of Jamie Langfield early in the second half.
Niall McGinn pulled one back for Aberdeen but the visitors could not find a leveller.
Aberdeen went into the match knowing victory would move them above Scottish Premier League leaders Celtic.
And while the Dons enjoyed plenty of possession and territory in the first half, it was County who had the better first-half chances.
Grant Munro almost got a telling touch on Richard Brittain's inswinging free-kick before Brittain fired over from 35 yards.
Langfield came under pressure after dithering on a passback and his attempted clearance was straight at the onrushing Rocco Quinn.
However, Langfield reacted quickly to palm away the County midfielder's header.
Niall McGinn had a shot blocked inside the hosts' penalty area before County opened the scoring.
Another searching Brittain free-kick into a crowded area was nodded past Langfield by Reynolds.
The Dons were quickly presented with an excellent chance to level as Marc Fitzpatrick's wayward header across his own box was intercepted by Rae and the midfielder's curling strike rattled the bar.
And another mistake, this time a short Brittain passback, sent Vernon through on goal but the striker stabbed his shot wide as Michael Fraser raced from his line.
Aberdeen continued to press at the start of the second half and Russell Anderson's low shot was blocked after the captain had wandered forward from defence.
And County soon doubled their lead with Ross latching on to Brittain's through pass and confidently beating Langfield.
However Aberdeen responded, and after Vernon had headed wide his replacement Jonny Hayes weaved his way to the byeline to set up the in-form McGinn for an easy tap-in.
The Dons continued to press but their chances of avoiding a first league defeat since the opening day of the season ended when Rae headed wide in injury time.
And County's win moves them level on points with seventh-place Kilmarnock.