It was no more than Motherwell deserved for a performance that made you wonder if these were the same players that did so poorly under Ian Barraclough and if, with a little bit of luck, his successor Mark McGhee could have been celebrating a first win rather than a first point since returning.
Only a sequence of stunning saves from Liverpool’s on-loan goalkeeper Danny Ward prevented the Dons from suffering a fifth successive defeat as the confidence that visibly returned to the side when Adam Rooney scored in 43 minutes just as noticeably drained away again when McDonald struck.
In between, Aberdeen attacked with a verve and penetration more reminiscent of the team who only last month defeated Celtic with just ten men and took Hearts apart at Tynecastle on the way to opening up a five-point lead at the top of the table.
Peter Pawlett should have scored on a couple of occasions during that spell, Niall McGinn was tantalisingly close to doing so and Mark Reynolds had the ball in the Motherwell net, only to fall foul of a dubious offside decision that left Derek McInnes smouldering with indignation.
Much more concerning for the Aberdeen manager was the way his side surrendered the goal that left them with just one point from the last 12 available as once again they were undone by a simple set-piece, with the diminutive McDonald nipping between defenders to glance in a Lionel Ainsworth free kick. That was similar to Rooney’s seventh goal of the season, a free-kick manoeuvre straight from the training ground that left the Motherwell manager moaning that on this occasion the assistant referee kept the flag down.
The goalscorer was just happy to get his third from open play after a frustrating start to the season in which the Irishman has had to get used to being rotated in the starting line-up along with the much less prolific David Goodwillie. It would be a surprise if the latter gets the nod on Saturday at Celtic Park, where Aberdeen really have to snap an astonishing 20-game losing streak in the league dating back to October 2004 if the title race is not going to be over by Christmas.
Rooney, for one, is undaunted by the task ahead and said: “It’s a tough place to go but we have beaten them down there in a cup game since I’ve been here and it holds no fear for us going there.”