A Louis Moult double helped Motherwell record an impressive 2-0 win against Aberdeen at Pittodrie.
Moult nodded home the opener three minutes before the break and was back on the scoresheet early in the second half to take his goal tally to 14 for the season.
The 25-year-old Englishman, a summer transfer target for the Dons, had netted a double when the Steelmen defeated the Dons 3-0 in the quarter-finals of the Betfred Cup.
The result leaves the Dons six points adrift of Scottish Premiership leaders Celtic.
The Dons made three alterations from the side that was held to a 2-2 draw by Hamilton Accies before the international break.
Stevie May and Greg Stewart were benched, while Graeme Shinnie missed out through suspension with Derek McInnes handing starts to Andrew Considine, Adam Rooney and Greg Tansey.
Considine wore the armband for the Dons on the day he moved up to sixth in Aberdeen’s all-time appearance chart with his 408th match for the Dons – one more than former teammate Russell Anderson.
Motherwell, in their final match before the Betfred Cup final, named a strong line-up with two changes from the team beaten 3-2 by Ross County. Ryan Bowman and Liam Grimshaw returned with Craig Tanner and Elliott Frear dropping out.
The Dons carved up two early openings inside five minutes with Rooney flicking wide before a Ryan Christie effort was easily held by Trevor Carson.
But it was the visitors who looked more threatening with a Liam Grimshaw half-volley well saved by Joe Lewis before the Aberdeen goalkeeper blocked a powerful Andy Rose drive.
The visitors went even closer in the 11th minute when a goal-bound shot by Rose was tipped away by the Dons number one, who was coping with a busy start to the afternoon.
Motherwell took the lead three minutes before the break when the visitors took advantage of some overly generous defending from the hosts. A long, diagonal Richard Tait free kick travelled 40 yards before being met by the unmarked Moult who headed the ball back across Lewis and into the far corner of the net.
After such an abject first half display, it was no surprise to see the Dons make a change at the break with Tansey replaced by May.
But it got even worse for the Dons 10 minutes into the second half when Chris Cadden showed great pace to skip past Scott McKenna before crossing for Moult who smashed the ball into the roof of the net from five yards out.
The Dons went close to pulling one back after 72 minutes when Scott Wright crossed for fellow substitute May but the former St Johnstone player could find no way past Carson.